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1.
Front Cell Dev Biol ; 9: 687868, 2021.
Article in English | MEDLINE | ID: mdl-34368136

ABSTRACT

OBJECTIVES: Exposure to chronic psychosocial stress is a risk factor for atherosclerotic cardiovascular diseases. Given that the 3-hydroxy-3-methylglutaryl-coenzyme reductase inhibitor statins prevent atherogenesis, we evaluated whether pitavastatin prevents chronic stress- and high fat diet-induced vascular senescence and atherogenesis in apolipoprotein E-deficient (ApoE -/-) mice, with a special focus on glucagon-like peptide-1 (GLP-1)/adiponectin (APN) axis. METHODS AND RESULTS: 6-week-old ApoE -/- mice loaded a high-fat diet were randomly assigned into non-stress (n = 12) and stress (n = 13) groups for 12 weeks. Non-stress control mice were left undisturbed. Chronic stress accelerated high fat diet-induce arterial senescence and atherosclerotic plaque growth. The chronic stress lowered the levels of circulating GLP-1 as well as adipose and plasma APN. As compared with the stress alone mice, the pitavastatin-treated mice had reduced macrophage infiltration, elastin fragments, and increased plaque collagen volume, and lowered levels of osteopontin, toll-like receptor-2/-4, macrophage chemoattractant protein-1, C-X-C chemokine receptor-4, p47 phox , p47 phox , gp91 phox , cathepsins S, p16, and p21, mRNAs and/or proteins. Pitavastatin increased plasma GLP-1 and APN levels and suppressed matrix metalloproteinase-2/-9 gene expressions and activities in the aortas. Finally, the protective effect of pitavastatin was abrogated by APN blocking. CONCLUSION: These findings suggested that the pitavastatin-mediated pleiotropic vasculoprotective effects are likely attributable, at least in part, to the elevation of GLP-1 and APN levels and the inhibition of diet-induced plaque inflammation, oxidative stress, and proteolysis in ApoE -/- mice received chronic stress conditions.

2.
Infect Drug Resist ; 13: 1575-1581, 2020.
Article in English | MEDLINE | ID: mdl-32547127

ABSTRACT

BACKGROUND: Infections caused by the carbapenem-resistant Enterobacter cloacae (CREC) bring great challenges to the clinical treatment and pose a serious threat to public health. In this study, we investigated the molecular characteristics of CREC in a tertiary hospital. MATERIALS AND METHODS: A total of 12 non-duplicate CREC strains isolated during the period of November 2016 to July 2019 were subjected to automated microbial identification and antimicrobial susceptibility testing (AST) using the BD Phoenix-100 identification and antimicrobial susceptibility testing (ID/AST) system. The strains were also subjected to phenotypic screening for the detection of antibiotic resistance genes such as the carbapenemase and other ß-lactamase genes, with the use of the polymerase chain reaction assay (PCR). Finally, multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE)-based homology analysis were applied. RESULTS: Four types of carbapenemases namely IMP-26, NDM-5, NDM-1, and KPC-2 were identified in 12 CREC strains. IMP-26 was the most prevalent type (6/12 strains, 50 %), followed by NDM-5 (3/12 strains, 25 %). The results of MLST revealed that these 12 strains could be divided into five sequence types (STs) among which ST544 was the dominant type (6/12 strains, 50 %). The PFGE results divided the 12 strains into four clusters. CONCLUSION: Our study indicated that the epidemics of the IMP-26-producing E. cloacae ST544 strain did occur in the intensive care unit (ICU) of a tertiary hospital. Therefore, early surveillance and strict implementation of control measures are crucial for the prevention of nosocomial infections and transmissions in hospitals.

3.
Int J Clin Exp Pathol ; 12(8): 3063-3069, 2019.
Article in English | MEDLINE | ID: mdl-31934146

ABSTRACT

BACKGROUND & AIMS: Primary hepatic cancer (PHC) is a common malignant tumor and the third most frequent cause of cancer-related death worldwide. However, the molecular mechanisms underlying hepatic cancer remain unknown. CTSB is considered a biomarker of cancer as it can facilitate tumor progression. We aimed to investigate the association between genetic polymorphisms of potential regulatory SNPs in the CTSB gene and PHC. METHODS: The relationship between CTSB rs12898 and PHC was analyzed in a case-control study with a Chinese population of 608 PHC patients and 608 healthy individuals using SPSS 21.0. RESULTS: PHC was significantly associated with alcohol consumption (P < 0.001), history of hepatitis (P < 0.001), and liver cirrhosis (P < 0.001), but not with smoking (P = 0.168), age (P = 0.175), or sex (P = 0.051). Distribution of three genotypes (GG, GA, and AA) of CTSB rs12898 significantly differed between the cases and controls (P < 0.001). Compared with the GG genotype, the GA and AA genotype was associated with a significantly increased risk of PHC (OR = 1.425, 95% CI = 1.099-1.848, P = 0.007; and OR = 2.220, 95% CI = 1.574-3.132, P < 0.001, respectively). CTSB rs12898 was associated with a significantly increased risk of PHC under a dominant model (OR = 1.592, 95% CI = 1.243-2.040, P < 0.001), and under a recessive model (OR = 1.771, 95% CI = 1.311-2.393, P < 0.001) for the variant A allele. CONCLUSION: Results suggest that CTSB rs12898G > A may play a role in the pathogenesis of PHC, and may be a marker for susceptibility to PHC.

4.
Med Sci Monit ; 24: 7186-7198, 2018 Oct 08.
Article in English | MEDLINE | ID: mdl-30296789

ABSTRACT

BACKGROUND This study investigated the role and mechanism of alprostadil in acute respiratory distress syndrome (ARDS) induced by oleic acid (OA) in rats. MATERIAL AND METHODS Sprague-Dawley rats were randomly divided into control, OA model, and OA + Alprostadil (2.5, 5, and 10 µg/kg, respectively) groups. The ARDS model was induced by femoral vein injection of OA, and alprostadil was administrated immediately. Lung injury was evaluated by lung wet-dry weight ratio (W/D) and histological analyses. Expressions of ACE, inflammatory mediators, apoptotic-related proteins, and proteins in the MAPKs and NF-κB signaling pathways were determined by Western blot or immunohistochemical staining. RESULTS Compared with the control group, the OA model group had significantly increased W/D, lung injury score, and collagen deposition at 3 h after OA injection. However, alprostadil (10 µg/kg) treatment significantly reduced OA-induced elevation of these indicators. Additionally, OA-induced expression of TNF-α and IL-1ß were suppressed by alprostadil. The OA-induced activation of nuclear factor (NF) κB p65 was also reduced by alprostadil. Furthermore, we found that Alprostadil had an inhibitory effect on the phosphorylation of JNK, ERK1/2, and p38 MAPKs. Alprostadil inhibited Bax but increased Bcl-2, indicating a suppressive role in apoptosis. Remarkably increased expression of ACE in the OA model group was observed, which was decreased by alprostadil. CONCLUSIONS Alprostadil has a protective effect on ARDS induced by OA in rats, possibly through inhibiting apoptosis, suppressing the activation of MAPKs and NF-κB signaling pathways, and decreasing ACE protein expression. Therefore, the use of alprostadil in clinical ARDS treatment is promising.


Subject(s)
Alprostadil/pharmacology , Respiratory Distress Syndrome/drug therapy , Animals , Apoptosis/drug effects , Bronchoalveolar Lavage Fluid/cytology , Disease Models, Animal , Lung/drug effects , Lung/pathology , Male , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/metabolism , Oleic Acid/toxicity , Random Allocation , Rats , Rats, Sprague-Dawley , Respiratory Distress Syndrome/chemically induced , Respiratory Distress Syndrome/metabolism , Respiratory Distress Syndrome/pathology , Signal Transduction/drug effects
5.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 30(8): 764-767, 2018 Aug.
Article in Chinese | MEDLINE | ID: mdl-30220278

ABSTRACT

OBJECTIVE: To investigate the anti-inflammatory effect of penehyclidine hydrochloride on oleic acid-induced acute respiratory distress syndrome (ARDS) in rats. METHODS: According to randomize number table method, 30 adult male Sprague-Dawley (SD) rats were divided into control group, model group and treatment group. Catheters were placed in femoral vein in each group. The control group was injected with 1.1 mL/kg physiological saline; the model group was injected with 0.1 mL/kg oleic acid and then injected with 1.0 mL/kg normal saline to establish ARDS model; the treatment group was injected with 0.1 mL/kg oleic acid and then injected with 1.0 mL/kg penehyclidine hydrochloride. At 3 hours after the model was established, blood gas analysis was carried out in each group, oxygenation index (PaO2/FiO2) was calculated, and the levels of serum interleukins (IL-1, IL-6) were measured by enzyme linked immunosorbent assay (ELISA). Rats were sacrificed to harvest lung tissue, and the lung wet/dry ratio (W/D) was calculated; the morphological changes of lung tissue was observed under microscope; the superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were detected by colorimetry; the expression of tumor necrosis factor -α (TNF-α) in lung tissue was detected by immunohistochemical method. The correlations between lung W/D ratio and various indicators were analyzed using Pearson correlation test. RESULTS: Compared with the control group, PaO2/FiO2 in model group was significantly decreased, lung W/D ratio was significantly increased, serum IL-1, IL-6 levels and lung tissue MDA content were significantly increased, lung tissue SOD activity was significantly decreased; the alveolar space was filled with exudate, neutrophils and red blood cells, and there were obvious edema and broadening in pulmonary interstitial and alveolar under light microscope; the type II alveolar epithelial cells were partly destroyed, accompanied by lamellar body degeneration and emptying phenomenon under electron microscope; and immunohistochemistry showed that the positive expression of TNF-α in lung tissue was significantly increased. Compared with the model group, PaO2/FiO2 in the treatment group was significantly improved [mmHg (1 mmHg = 0.133 kPa): 204.42±31.61 vs. 113.91±47.78, P < 0.05], the lung W/D ratio was significantly decreased (5.80±0.44 vs. 6.82±0.59, P < 0.01), serum IL-1, IL-6 levels and lung tissue MDA content were significantly decreased [IL-1 (µg/L): 18.38±0.28 vs. 20.04±0.39, IL-6 (µg/L): 12.64±0.67 vs. 14.28±1.33, MDA (nmol/mg): 3.95±0.28 vs. 5.17±0.29, all P < 0.05], the activity of SOD in lung tissue was significantly increased (U/mg: 48.75±2.41 vs. 45.09±1.69, P < 0.01), histological and pathological changes were significantly reduced, and the positive expression of TNF-α in lung tissue was significantly reduced [positive cell rate: (25.80±3.44)% vs. (38.82±3.59)%, P < 0.01]. CONCLUSIONS: Penehyclidine hydrochloride can effectively improve the oxygenation, alleviate lung injury and reduce pulmonary edema in oleic acid induced ARDS rat by decreasing lung W/D ratio, inhibiting oxidative stress and inflammatory response.


Subject(s)
Lung Diseases , Animals , Lung , Male , Quinuclidines , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha
6.
Nano Lett ; 18(2): 1428-1434, 2018 02 14.
Article in English | MEDLINE | ID: mdl-29297693

ABSTRACT

We present temperature-dependent resonance Raman measurements on monolayer WS2 for the temperature range 4-295 K using excitation photon energies from 1.9 to 2.15 eV in ∼7 meV steps. These are analyzed to determine the resonance profiles of five previously assigned phonon based Raman peaks (A1', E', 2ZA, LA, 2LA) and a previously unassigned peak at 485 cm-1 whose possible attributions are discussed. The resonance profiles obtained are fitted to a perturbation theory derived model and it is shown that both excitons and trions are required to explain the profiles. The model is used to separate the contribution of exciton-exciton, trion-trion, and exciton-trion scattering to each of the Raman peaks at 4 K. This separation allows the ratios of the rates of scattering involving the A1' and E' phonons for each of the three types of scattering to be determined. The explanation of the multiphonon Raman peaks requires the coupling of bright excitons and trions to large wavevector dark states. The fitting of the resonance Raman profiles for these Raman peaks demonstrates scattering of bright excitons to bright trions via these large wavevector dark states.

7.
ACS Appl Mater Interfaces ; 8(50): 34552-34558, 2016 Dec 21.
Article in English | MEDLINE | ID: mdl-27998149

ABSTRACT

We present a new and viable template-assisted thermal synthesis method for preparing amorphous ultrathin transition-metal oxides (TMOs) such as TiO2 and Ta2O5, which are converted from crystalline two-dimensional (2D) transition-metal dichalcogenides (TMDs) down to a few atomic layers. X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning transmission electron microscopy (STEM) were used to characterize the chemical composition and bonding, surface morphology, and atomic structure of these ultrathin amorphous materials to validate the effectiveness of our synthesis approach. Furthermore, we have fabricated metal-insulator-metal (MIM) diodes using the TiO2 and Ta2O5 as ultrathin insulating layers with low potential barrier heights. Our MIM diodes show a clear transition from direct tunneling to Fowler-Nordheim tunneling, which was not observed in previously reported MIM diodes with TiO2 or Ta2O5 as the insulating layer. We attribute the improved performance of our MIM diodes to the excellent flatness and low pinhole/defect densities in our TMO insulting layers converted from 2D TMDs, which enable the low-threshold and controllable electron tunneling transport. We envision that it is possible to use the ultrathin TMOs converted from 2D TMDs as the insulating layer of a wide variety of metal-insulator and field-effect electronic devices for various applications ranging from microwave mixing, parametric conversion, infrared photodetection, emissive energy harvesting, to ultrafast electronic switching.

8.
Sensors (Basel) ; 15(4): 8163-72, 2015 Apr 08.
Article in English | MEDLINE | ID: mdl-25856327

ABSTRACT

The impact wave response of soil due to a ball drop is monitored on a 30.5 cm by 30.5 cm square soil box using a fiber sensor with dynamic strain sensing capability. The experiments are conducted in real time using a simple one-laser one-modulator configuration with stimulated Brillouin scattering. The embedded BOTDA sensor grid successfully monitored the distribution and evolution of the inner strains of a sand bed during a mass impact on its surface. The measurement of the distributed dynamic strains was possible in several milliseconds and with 1 cm actual location resolution. This paper presents a time-domain signal analysis utilized for determining the dynamic strains in embedded fiber sensor. The results demonstrate the method to be a promising one for detection of subsurface vibration and movement in geotechnical Structure Health Monitoring (SHM).

9.
Appl Opt ; 48(30): 5823-8, 2009 Oct 20.
Article in English | MEDLINE | ID: mdl-19844320

ABSTRACT

In recent years, several distributed sensor systems based on stimulated Brillouin scattering in optical fibers have been proposed [J. Intell. Mater. Syst. Struct.10, 340 (1999); Proc. SPIE5855, 555 (2005)]. We propose a simpler scheme based on fiber-end reflection and Brillouin gain spectrum analysis. In this setup, only one optical source is necessary to provide both the pump and the probe wave; the latter is provided by the modulated pulse base. First, the physical mechanisms for two different Brillouin scattering processes in our sensor system are analyzed and an approximate theory model is proposed. In addition, it is demonstrated that the simple system configuration allows simultaneous acquisition of the time-domain and the frequency-domain information. It is experimentally demonstrated that this configuration is effective for strain measurements and could as well be applied to temperature monitoring.

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