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1.
J Nanosci Nanotechnol ; 20(2): 941-948, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383090

RESUMO

To synthesize and investigate the two kinds of nanoparticles (Al2O3 and CuO) dispersed into R141b, nanorefrigerants with the concentrations from 0.5 to 2.4 vol.% were prepared. Thermophysical properties at temperatures from 6 to 22 °C were checked, long-term stability of the nanorefrigerants was also investigated. Results showed that, density and viscosity increased with the increase in nanoparticle volume fractions, however, they decreased with the increase in temperature. Thermal conductivity and thermal diffusivity increased with the augmentation of particle concentration and temperature. Specific heat capacity increased with the increase in temperature, and decreased with the increase in volume fraction of nanoparticles. Based on the measured properties, heat transfer coefficient ratio was calculated to evaluate the heat transfer performance of the nanorefrigerants. Finally, Al2O3/R141b nanorefrigerant with 1.2 vol.% was selected as the optimal nanorefrigerant for ORC.

2.
Appl Opt ; 58(27): 7424-7429, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31674391

RESUMO

The photonic crystal fiber (PCF) with better thermal stability and polarization-maintaining performance is applied to the resonant fiber optic gyroscope (RFOG). A hybrid fiber ring resonator is fabricated using the conventional polarization-maintaining fiber (PMF) and PCF with close mode field diameters (MFDs) to reduce MFD-mismatch-induced splicing loss. Furthermore, the temperature-dependent birefringence coefficients of the PMF and the PCF are measured to differ almost four times in absolute value and be opposite in sign. The polarization stability of the hybrid PCF-PMF ring resonator is improved by a factor of 7 compared with the PMF ring resonator with the same length of PMF. The RFOG equipped with this hybrid PCF-PMF ring resonator achieves a bias stability of 1.67°/h.

3.
Mol Ther Nucleic Acids ; 18: 554-566, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31675668

RESUMO

Previously, our transcriptome sequencing revealed that lnc9141 was differentially expressed in muscles of fetal bovine, calf, and adult bovine, which is considered to provide the basis for raising the muscle mass. In this study, we identified lnc9141 characters. lnc9141 has different transcription start sites and 3' alternative splicing sites of exon 1, producing lnc9141-a and lnc9141-b transcripts that were highly expressed in the heart and lung. Moreover, neither lnc9141-a nor lnc9141-b had the ability to encode proteins. The functions of lnc9141-a and lnc9141-b were explored by cell cycle, 5-ethynyl-2'-deoxyuridine (EdU), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed that lnc9141-a or lnc9141-b overexpression decreased the number of myoblasts in the S phase and increased the proportion of cells in the G0/G1 phase. Furthermore, overexpressing lnc9141-a and lnc9141-b respectively downregulated the expression of CyclinD1. However, lnc9141-a or lnc9141-b interference was found to increase the number of S-phase myoblasts, and upregulate Cyclin D1 and Cyclin E expression. Through Annexin V-FITC/propidium iodide (PI) double staining and the expression of apoptosis marker genes (Bax, Bcl2, and Caspase-3), it was found that lnc9141-b could regulate the expression of Bax gene. Meantime, high expression of lnc9141-b could decrease MyHC expression. In addition, the intergenic region between lnc9141 and IRX5 was 2.3 kb, with a head-to-head orientation. The study also revealed the core regions of the lnc9141 and IRX5 promoter. Our study demonstrated that both lnc9141-a and -b expression inhibited bovine myoblast proliferation. However, lnc9141-b regulated Bax and MyHC expression. The regulatory mechanism of lnc9141-a and lnc9141-b needs to be further explored.

4.
Chem Biol Interact ; 315: 108869, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31682803

RESUMO

Spermatogenic dysfunction is one of the major secondary complications of male diabetes. Salidroside (SAL) is the important active ingredients isolated from Herba Cistanche, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. The present study was designed to determine whether SAL contributes to the recovery from spermatogenic dysfunction in streptozotocin (STZ) induced type-1 diabetic mice. SAL (25, 50, or 100 mg/kg) and Clomiphene citrate (CC, 5 mg/kg) were orally administered to male type-1 diabetic mice for 10 weeks. Testis tissues were collected for histopathological and biochemical analysis. Moreover, reproductive organ weight, sperm parameters, and testicular cell DNA damage were estimated. The results revealed that SAL significantly improved the weight of the reproductive organs, sperm parameters and testicular morphology to different degrees in type-1 diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked downregulation the fluorescence expressions of p38 MAPK phosphorylation and upregulation the protein expressions of ZO-1, Occludin, Claudin-11 and N-cadherin after SAL administration (100 mg/kg) compared with the type-1 diabetic group. In conclusion, these results demonstrated that SAL exerts protective effects on type-1 diabetes-induced male spermatogenic dysfunction, which is likely mediated by inhibiting oxidative stress-mediated blood testis barrier damage.

5.
Dermatol Ther ; : e13153, 2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31705602

RESUMO

In order to investigate the effect of daily emollient treatment on infantile atopic dermatitis (AD) during the maintenance period, a total of 309 children younger than 2 years with moderate AD (155 and 154 in the treatment and control groups, respectively) were enrolled in this multicenter, randomized, parallel controlled clinical trial. Subjects were topically treated with desonide cream and emollients in Prinsepia utilis Royle for 2-4 weeks before entering the maintenance period and then differentially treated with either emollients for treatment or none for control. The cumulative maintenance rate, time to flare and improvement of eczema area and severity index (EASI) and infant's dermatitis quality of life index (IDQOL) were evaluated. Results showed that the cumulative maintenance rate of the treatment group (60.5%, 95% CI 50.0-69.4%) was significantly higher than that of the control group (23.5%, 95% CI 15.2-33.0%) (p < .001). The median time to flare in the treatment group was 90 days (interquartile range, IQR 28-90), which was significantly longer than that in the control group (28 days [IQR 18-67]) (p < .001). At Week 4 in the maintenance period, the EASI and IDQOL scores of the treatment group were lower than those of the control group. In conclusion, the application of emollients during the maintenance period of infantile AD can significantly reduce the risk of AD flares, prolong the time to flare and improve the clinical symptoms.

6.
Nanotechnology ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31711047

RESUMO

The dissolution and diffusion of polysulfides leading to inferior cycling performance are still the main bottleneck hindering commercialization of Li-S battery, although they have received many restrictive policies in recent years. Herein, a new strategy that lithium polyacrylate (LiPAA) was introduced to clad on multiwalled carbon nanotube/sulfur (MWNT/S) composites as the interface layer for MWNT/S/LiPAA cathode, was proposed to not only suppress polysulfides migration through physical encapsulation and chemical adsorption but also facilite Li+ diffusion during the charge-discharge process. Attributing to these functions of LiPAA, the MWNT/S/LiPAA exhibited the rate capability and cycling performance superior to MWNT/S and MWNT/S/PAA. Moreover, thanking to the introduction of LiPAA, the MWNT/S/LiPAA were endowed with robust mechanical property, which was qualified as flexible cathode to assemble flexible Li-S battery with stable output under deformation condition. This work would open up a promising way to suppress polysulfides migration for high-performance flexible Li-S battery.

7.
J Chemother ; : 1-11, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31724495

RESUMO

We assessed the expression of Serpin Family E Member 1 (SERPINE1) and its prognostic values in gastric adenocarcinoma (GAC) by using the data from TCGA database. The biological functions of SERPINE1 in GAC cells were detected by cell counting Kit-8, colony-forming, Transwell, and wound-healing assays, appropriately. Relative mRNA and protein levels were detected by RT-qPCR and western blot. Bioinformatics analysis indicated that SERPINE1 was significantly up-regulated in GAC tissues compared to normal tissues. High SERPINE1 expression led to a short overall survival and could act as an independent prognosticator for GAC patients. Besides, down-regulation of SERPINE1 showed a suppressive effect on the phenotype of GAC cells and significantly inhibited the EMT process. Over-expression of SERPINE1 got the reverse outcomes. These data suggest that SERPINE1 contributes to the proliferation, invasion and migration of GAC cells, insinuating that SERPINE1 may be considered as a novel biomarker for GAC treatment.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31760420

RESUMO

CONTEXT: Thyroid autoimmunity (TAI), the most common cause of (sub)clinical hypothyroidism, is associated with adverse pregnancy outcomes. The benefits of levothyroxine (LT4) intervention in women with TAI remain controversial. OBJECTIVE: To determine the effect of LT4 on pregnancy outcomes in euthyroid women with TAI. CONCLUSION: No definitive evidence showed improvement of pregnancy outcomes with LT4 supplementation in euthyroid women with TAI. However, therapeutic strategies, especially dosages and initial times of intervention, may be of great importance. Additional large RCTs are needed in the future.

9.
Nanotechnology ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31726430

RESUMO

Though secondary batteries widely existed in many fields, new electrode materials with reasonable structure are desired for high battery performance. Herein, Sb/nitrogen-doped graphene nanosheets (NGNS-Q) was constructed with the help of 7,7,8,8-tetracyanoquinodimethane anion (TCNQ∙-). TCNQ∙- was used to anchor Sb3+ into the graphene layer with the electrostatic interaction, which improves the distribution of Sb nanoparticles. Meanwhile, TCNQ∙- acts as a nitrogen source to form N doped graphene, enhancing the electron conductivity of the composite. Benefiting from the stable structure and good conductivity, the Sb/NGNS-Q composite achieved good electrochemical battery performance for Li/Na ion batteries (LIBs/SIBs). At the current density of 0.1 A g-1, the Sb/NGNS-Q exhibited 615 mAh g-1 after cycling 200 times and 240 mAh g-1 after 100 cycles for LIBs and SIBs, respectively.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31595767

RESUMO

In recent ten years, the sexual contact transmission has led to the consecutive upsurge of HIV in Hebei. Especially, the risk behaviors of homosexual contact in Hebei has presented challenges for HIV prevention and treatment efforts. In this study, we found that 98.9% of subjects attributed their HIV-1 infections to sexual contact, and MSM accounted for 77.5%. CRF01_AE (49.6%), CRF07_BC (29.7%) and subtype B (13.0%) was three main genotypes. AE_cluster 1 (73 cases), AE_cluster 2 (62 cases) and one large 07_BC cluster (75 cases) were identified, and only closely clustered with MSM sequences from Beijing. Further, all of HIV-1 resistant strains were circulating in transmission clusters. Particularly, 76.5% of subjects resistant to drugs were circulating in above three large transmission clusters associated with MSM from Beijing. Our study proved that the busy movement of MSM between Beijing and Hebei could meet conveniently, which might result in the bidirectional exchange of HIV-1 strains between Beijing and Hebei. As the most frequent genotypes, large transmission clusters associated with CRF01_AE and CRF07_BC have become one of main factors resulting in the rapid increase of HIV in Hebei. Therefore, the enhanced surveillance for HIV should be planned early among the floating population travelling between Beijing and Hebei. Hebei should construct the cooperative mechanism for HIV prevention and control together with Beijing.

11.
Eur J Radiol ; 120: 108685, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31606712

RESUMO

PURPOSE: This study explored the interreader agreement and diagnostic performance of contrast-enhanced ultrasound liver imaging reporting and data system (CEUS LI-RADS). METHODS: Between January 2014 and December 2017, 1366 patients at risk for hepatocellular carcinoma (HCC) who underwent CEUS were included in this retrospective study. Four ultrasound physicians rated the HCC likelihood of focal liver lesions (FLLs) using CEUS LI-RADS v2017. Interreader agreement on CEUS LI-RADS categories and major features (arterial phase hyperenhancement (APHE), washout appearance) were assessed using weighted kappa statistics (κ). Diagnostic performance was described by sensitivity, specificity, PPV and NPV, +LR, -LR. RESULTS: The interreader agreement (κ) for CEUS LI-RADS categories, APHE, and washout appearance ranged from 0.61 to 0.73, 0.65 to 0.83, and 0.58 to 0.71, respectively. Interreader agreement for LI-RADS categories and APHE were almost substantial between FLLs <2 cm, ≥2 cm, <5 cm; interreader agreement for major features were fair to substantial for FLLs ≥5 cm. The accuracy, PPV and + LR for HCC and malignancy in FLLs <2 cm, ≥2 cm, <5 cm, ≥5 cm were high, with values of 84.7% to 91.9%, 90.2% to 94.2%, and 2.2 to 8.0, respectively. CEUS LI-RADS had the highest specificity for HCC (90.2%) and malignancy (90.9%) diagnosis for FLLs <2 cm and <5 cm, respectively; specificity was lowest for HCC (54.7%) and malignancy (68.3%) diagnosis for FLLs ≥5 cm. CONCLUSIONS: CEUS LI-RADS is a good standardized categorization system for high-risk patients, and the combination of two or three LR-M features may improve the true-negative classification of HCC diagnosis.

14.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117607, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31654846

RESUMO

The level of alkaline phosphate (ALP) is a significant biomarker index in organism. In this work, a label-free and sensitive G-quadruplex fluorescence assay for monitoring ALP activity has been developed with the assistance of Cu2+ based on the competitive binding effect between pyrophosphate (PPi) and G-quadruplex-N-methylmesoporphyrin (G4/NMM) complex to Cu2+. In the sensing assay, the G4/NMM complex is employed as a signal indicator, while the Cu2+ as a quencher and the PPi as recovery agent as well as the hydrolytic substance for ALP. In details, the fluorescence of the G4/NMM complex was efficiently quenched by introducing Cu2+ due to the proximal carboxylate groups of NMM coordinating with the Cu2+ as well as the unfolding of G-quadruplex by Cu2+, while the higher affinity between PPi and Cu2+ could lead to the fluorescence recovery. However, in the presence of ALP, the PPi was hydrolyzed to phosphate ions (Pi) which cannot integrate with Cu2+, resulting in the fluorescence quenching once again. Thus, a simple and facile way to inspect ALP has been exploited. The proposed assay shows a good linear relationship in the range from 0.5 to 100 U/L with the detection limit of 0.3 U/L. Moreover, the fabricated method is succeeded in detecting ALP in human serum samples, indicating the potential as a profitable candidate in biological and biomedical application.

16.
Biomed Pharmacother ; 120: 109487, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31577975

RESUMO

Heart failure (HF) leads to an increase in morbidity and mortality globally. Disorders of energy metabolism and apoptosis of cardiomyocytes are critically involved in the progression of HF. Ginsenoside Rb3 (G-Rb3) is a natural product derived from ginseng that has cardio-protective effect. The pharmacological mechanism of G-Rb3 in the treatment of HF remains to be clarified. In this study, we aimed to explore the regulative effects of G-Rb3 on fatty acids oxidation and apoptosis by in vivo and in vitro studies. Myocardial infarction (MI)-induced HF mice model and a cellular H9C2 injury model was induced by oxygen-glucose deprivation/reperfusion (OGD/R) stimulation. The results showed that G-Rb3 could protect heart functions in MI-induced HF model. G-Rb3 treatment up-regulated expressions of key enzymes involved in ß-oxidation of fatty acids, including carnitine palmitoyltransterase-1α (CPT-1α), acyl-CoA dehydrogenase long chain (ACADL) and the major mitochondrial deacetylase enzyme sirtuin 3 (SIRT3). The upstream transcriptional regulator, peroxisome proliferator-activated receptor α (PPARα), was also up-regulated by G-Rb3 treatment. In vitro study demonstrated that G-Rb3 could protect mitochondrial membrane integrity and exert anti-apoptotic effects, in addition to regulating fatty acids oxidation. Impressively, after cells were co-treated with PPARα inhibitor, the regulative effects of G-Rb3 on energy metabolism and apoptosis were abrogated. Our study suggests that G-Rb3 is a promising agent and PPARα is potential target in the management of HF.

17.
Biomed Pharmacother ; 120: 109474, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31585299

RESUMO

BACKGROUND: Blood-testis barrier (BTB) impairments is one of the major secondary complications of diabetes. Betaine (BET) is the important active ingredients isolated from Lycium barbarum, which exhibits numerous pharmacological activities such as antioxidant, anti-diabetic, and anti-inflammatory effects. This study aimed to establish whether BET contributes to the recovery from BTB dysfunction in streptozotocin (STZ) induced diabetic mice. METHODS: BET (200, 400, 800 mg/kg) was orally administered to diabetic mice for 8 weeks. Testis tissues were collected for histopathological and biochemical analysis, the reproductive organ weight was estimated. Antioxidant enzyme activity and BTB associated protein expressions were determined with their corresponding assay kits and western blot analysis. The results revealed that BET significantly improved the weight of the reproductive organs and testicular morphology in diabetic mice. Furthermore, reactive oxygen species (ROS) and malondialdehyde (MDA) levels were significantly reduced, and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), markedly increased in the testicular tissue after SAL treatment. In addition, our data also showed a marked down-regulated the expressions of p38 MAPK phosphorylation and up-regulation the protein expressions of ZO-1, Occludin, Claudin-11, N-cadherin, and Connexin-43 after BET administration compared with the diabetic group. In conclusion, these results demonstrated that BET exerts protective effects on diabetes-induced BTB dysfunction, which may be through regulating oxidative stress-mediated p38 MAPK pathways.

18.
Breast Cancer Res ; 21(1): 118, 2019 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660981

RESUMO

BACKGROUND: Given that breast cancer and normal dense fibroglandular tissue have similar radiographic attenuation, we examine whether automated volumetric density measures identify a differential change between breasts in women with cancer and compare to healthy controls. METHODS: Eligible cases (n = 1160) had unilateral invasive breast cancer and bilateral full-field digital mammograms (FFDMs) at two time points: within 2 months and 1-5 years before diagnosis. Controls (n = 2360) were matched to cases on age and date of FFDMs. Dense volume (DV) and volumetric percent density (VPD) for each breast were assessed using Volpara™. Differences in DV and VPD between mammograms (median 3 years apart) were calculated per breast separately for cases and controls and their difference evaluated by using the Wilcoxon signed-rank test. To simulate clinical practice where cancer laterality is unknown, we examined whether the absolute difference between breasts can discriminate cases from controls using area under the ROC curve (AUC) analysis, adjusting for age, BMI, and time. RESULTS: Among cases, the VPD and DV between mammograms of the cancerous breast decreased to a lesser degree (- 0.26% and - 2.10 cm3) than the normal breast (- 0.39% and - 2.74 cm3) for a difference of 0.13% (p value < 0.001) and 0.63 cm3 (p = 0.002), respectively. Among controls, the differences between breasts were nearly identical for VPD (- 0.02 [p = 0.92]) and DV (0.05 [p = 0.77]). The AUC for discriminating cases from controls using absolute difference between breasts was 0.54 (95% CI 0.52, 0.56) for VPD and 0.56 (95% CI, 0.54, 0.58) for DV. CONCLUSION: There is a small relative increase in volumetric density measures over time in the breast with cancer which is not found in the normal breast. However, the magnitude of this difference is small, and this measure alone does not appear to be a good discriminator between women with and without breast cancer.

19.
Nutrients ; 11(10)2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31597293

RESUMO

Human milk oligosaccharides (HMOs), phospholipids (PLs), and gangliosides (GAs) are components of human breast milk that play important roles in the development of the rapidly growing infant. The differences in these components in human milk from the United Arab Emirates (UAE) were studied in a cross-sectional trial. High-performance liquid chromatography‒mass spectrometry was used to determine HMO, PL, and GA concentrations in transitional (5-15 days) and mature (at 6 months post-partum) breast milk of mothers of the United Arab Emirates (UAE). The results showed that the average HMO (12 species), PL (7 species), and GA (2 species) concentrations quantified in the UAE mothers' transitional milk samples were (in mg/L) 8204 ± 2389, 269 ± 89, and 21.18 ± 11.46, respectively, while in mature milk, the respective concentrations were (in mg/L) 3905 ± 1466, 220 ± 85, and 20.18 ± 9.75. The individual HMO concentrations measured in this study were all significantly higher in transitional milk than in mature milk, except for 3 fucosyllactose, which was higher in mature milk. In this study, secretor and non-secretor phenotype mothers showed no significant difference in the total HMO concentration. For the PL and GA components, changes in the individual PL and GA species distribution was observed between transitional milk and mature milk. However, the changes were within the ranges found in human milk from other regions.

20.
Int J Neurosci ; : 1-3, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31613174

RESUMO

Introduction: Mitochondrial DNA polymerase gamma (pol γ) encoded by POLG plays an indispensable role in the process of mitochondrial DNA replication and repair. The mutation of POLG can result in mitochondrial dysfunction leading to a broad spectrum of disease.Methods: We report a 29-year-old Chinese female presented with levodopa-responsive parkinsonism, external ophthalmoplegia and optic atrophy. We conducted clinical, molecular iconographic, histological and genetic analyses on this patient.Results: Sequencing of the POLG gene revealed compound heterozygote mutations of a novel c.2693T > C (p.I898T) mutation in exon17 and c.2993C > T (p.S998L) in exon19. The mutation c.2693T > C (p.I898T) has never been reported. Also our patient's cardinal symptoms are rare and different from other cases which have been reported.Conclusion: This finding of ours has broadened the spectrum of phenotype caused by the mutation of POLG.

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