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1.
J Nanosci Nanotechnol ; 20(2): 779-788, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383073

RESUMO

N and F co-doped La-TiO2 (La-TONF) samples were prepared through the solvothermal method by using HMT and NaF as precursors. The obtained samples were characterized by UV-Vis DRS, XRD, XPS and PL measurements for light-harvesting properties, crystal phase and optical characteristics, respectively. Interestingly, the TONF sample had a different fluorescence emission intensity than the TON or TOF samples, thus suggesting a clear synergistic effect of N and F co-doping. The optimal doping amount of La was 2 wt.%, and the absorption edge was red-shifted from 453 nm to 464 nm for La-TiO2 and La-TONF. The photocatalytic activity was evaluated by degradation of MO and oxidation of TMB under visible light irradiation. La-TONF exhibited excellent photocatalytic activity and a degradation rate of 92.4%, 4.4 times that of undoped TiO2 (20.8%). The photocatalytic degradation activity remained above 85.8%, even after five runs. In addition, the MO photodegradation catalyzed by La-TONF followed first order kinetics. According these results, a possible synergistic effect mechanism for the enhanced photocatalytic performance is proposed.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117466, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31422340

RESUMO

Femtosecond time-resolved transient absorption spectroscopy is employed to investigate the ultrafast excited-state dynamics from the S2 state of dibenzofuran and the hydrogen bonding effect in protic and aprotic solvents. Following the excitation with 266 nm, the initial population on the S2 state couples to the S1 state via internal conversion on tens of picoseconds. Afterwards, vibrational energy relaxation (VER) with dozens of picoseconds is determined in all solvents and strongly depended on the polarities of aprotic solvents. And the rising species related with the hydrogen-bonded intermediate S⁎ state are observed just in ethanol and methanol with the higher Kamlet parameter α. Subsequently, the intersystem crossing from the S1 state to the triplet manifold is a main deactivation pathway with the decay time of ≫ns. All the relaxation processes exhibit solvent dependence, indicating that hydrogen bonding interaction between solute and solvent enhances VER and significantly influences on the excited state dynamics of dibenzofuran.

3.
Eur J Pharm Sci ; 142: 105100, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669385

RESUMO

Warfarin and ginseng have been widely used in the treatment of cardiovascular diseases. However, the clinical safety and effectiveness of herb-drug combination treatment are still controversial. Therefore, it is very essential to probe the interaction between warfarin and ginseng. In this study, in vitro and in vivo study was carried out to demonstrate that whether there is an interaction between warfarin and ginsenosides (GS), which is the main component of ginseng. In vitro study showed that the adhesion ability between endothelial cells and matrigel/platelets was enhanced due to the up-regulating expression of intercellular adhesion molecule (ICAM-1) and vascular cell adhesion molecule (VCAM-1) proteins by treatment of warfarin+GS combination compared to warfarin/GS treatment alone. Moreover, GS could weaken the anticoagulation effect of warfarin in hyperlipemia rats owning to the increased expression levels of coagulation factors and hepatic cytochrome P450 enzymes in plasma after long-term co-administration of warfarin with GS. The results of both in vitro and in vivo study demonstrated that there is a serious interaction between warfarin and ginseng, which may deteriorate atherosclerosis and thrombosis after combined use of warfarin and GS.

4.
Water Res ; 169: 115193, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31670083

RESUMO

The positive roles of N-acyl homoserine lactone (AHL)-mediated quorum sensing (QS) in aerobic granular sludge (AGS) have been widely acknowledged. However, it is not feasible to manipulate granulation via direct addition of AHL chemicals or AHL-producing strains. Here, several strains with high AHL-producing capacity were successfully isolated from AGS. These QS strains were cultivated, mixed as a consortium, and then divided into two groups: AHLs supernatant and bacterial cells encapsulated in sodium alginate (CEBs). The potential of QS regulation, via doses of AHLs supernatant and CEBs, in accelerating granulation was evaluated. Results clearly indicated that short-term (days 21-70) addition of AHLs supernatant led to a rapid specific growth rate (0.08 d-1), compact structure without filamentous bacteria overgrowth, excellent settlement performance (SVI10 37.2 mL/g), and a high integrity coefficient (4.4%) of the granules. Sustainable release of AHLs (mainly C6- and C8-HSL) was induced by exogenous AHLs, possibly attributed to the enrichment of the genera Aeromonas and Pseudomonas. Further, tryptophan and aromatic protein substances were produced to maintain structural stability, suggesting that short-term QS regulation had long-term positive effects on the characteristics of AGS. By comparison, the addition of CEBs posed negligible or negative impact on the granulation, as evidenced by the rupture of smaller aggregates and poor characteristics of AGS. Overall, augmentation of the signaling content via addition of AHLs supernatant from QS strains is an economical and feasible regulation strategy to accelerate granulation and sustain long-term structural stability.

5.
J Immunol ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776204

RESUMO

The African clawed frog, Xenopus laevis, is a model species for amphibians. Before metamorphosis, tadpoles do not efficiently express the single classical MHC class I (MHC-I) molecule Xela-UAA, but after metamorphosis, adults express this molecule in abundance. To elucidate the Ag-presenting mechanism of Xela-UAA, in this study, the Xela-UAA structure complex (pXela-UAAg) bound with a peptide from a synthetic random peptide library was determined. The amino acid homology between the Xela-UAA and MHC-I sequences of different species is <45%, and these differences are fully reflected in the three-dimensional structure of pXela-UAAg. Because of polymorphisms and interspecific differences in amino acid sequences, pXela-UAAg forms a distinct peptide-binding groove and presents a unique peptide profile. The most important feature of pXela-UAAg is the two-amino acid insertion in the α2-helical region, which forms a protrusion of ∼3.8 Å that is involved in TCR docking. Comparison of peptide-MHC-I complex (pMHC-I) structures showed that only four amino acids in ß2-microglobulin that were bound to MHC-I are conserved in almost all jawed vertebrates, and the most unique feature in nonmammalian pMHC-I molecules is that the AB loop bound ß2-microglobulin. Additionally, the binding distance between pMHC-I and CD8 molecules in nonmammals is different from that in mammals. These unique features of pXela-UAAg provide enhanced knowledge of T cell immunity and bridge the knowledge gap regarding the coevolutionary progression of the MHC-I complex from aquatic to terrestrial species.

6.
Lancet Planet Health ; 3(11): e478-e490, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31777339

RESUMO

BACKGROUND: The role of environmental exposures in chronic obstructive pulmonary disease (COPD) remains inconclusive. We examined the association between environmental exposures (PM2·5, greenness, and urbanicity) and COPD prevalence using the UK Biobank cohort data to identify key built environment correlates of COPD. METHODS: In this cross-sectional, observational study we used baseline data for UK Biobank participants. Included participants were aged 39 years and older, white, had available spirometry data, and had complete data for phenotypes and exposures. COPD was defined by spirometry with the 2017 Global Initiative for Chronic Obstructive Lung Disease criteria. Environmental exposures were PM2·5 derived from monitoring data and interpolated using land-use regression at the participants' geocoded residential addresses. Built environment metrics of residential greenness were modelled in terms of normalised difference vegetation index from remotely sensed colour infrared data within a 500 m residential catchment, and an urbanicity index derived from spatial analyses and measured with a 1 km buffer around each participant's residential address. Logistic regression models examined the associations between environmental exposures and COPD prevalence adjusting for a range of confounders. Subgroup analyses by urbanicity and effect modification by white blood cell count as an inflammatory marker were also done. FINDINGS: We assessed 96 779 participants recruited between April 4, 2006, and Oct 1, 2010, of which 5391 participants had COPD with a prevalence of 5·6%. Each 10 µg/m3 increment in ambient PM2·5 exposure at a participant's residential location was associated with higher odds of COPD (odds ratio 1·55, 95% CI 1·14-2·10). Among the built environment metrics, urbanicity was associated with higher odds of COPD (1·05, 1·01-1·08 per interquartile increment), whereas residential greenness was protective, being associated with lower odds of COPD (0·89, 0·84-0·93 for each interquartile increment in greenness). The results remained consistent in models of COPD defined as per lower limit of normal criteria. The highest quartile of white blood cell count was associated with lower lung function and higher COPD risk with a significant interaction between PM2·5 and white blood cell count only in the model of lung function (p=0·0003). INTERPRETATION: In this study of the built environment and COPD, to our knowledge the largest done in the UK, we found that exposure to ambient PM2·5 and urbanicity were associated with a higher risk of COPD. Residing in greener areas, as measured by normalised difference vegetation index, was associated with lower odds of COPD, suggesting the potential value of urban planning and design in minimising or offsetting environmental risks for the prevention and management of COPD. FUNDING: University of Hong Kong, UK Biobank, and UK Economic & Social Research Council.

7.
Water Res ; 169: 115276, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31731242

RESUMO

Wastewater treatment plants (WWTPs) are critical for maintaining sustainable development in modern societies, wherein microbial populations residing in activated sludge (AS) are responsible for the removal of pollutants from wastewater. The biodegradability [biological oxygen demand/chemical oxygen demand (B/C ratio)] of influent, as a measure of the degree of available energy and toxicity to microorganisms in AS, has been hypothesized to drive AS microbial community assembly. However, the validity of this hypothesis has not been tested in full-scale WWTPs. In this study, we assessed the pollutant removal loads, the microbial community diversity, the relative importance of deterministic and stochastic assembly processes, and bio-interactions within the communities by analyzing 195 AS samples comprising nearly 5 000 000 16S rRNA sequences. Our results indicate that the effects of B/C ratio on pollutant removal loads can be perfectly reflected through biological properties, implying that B/C ratio determined WWTPs performance through affecting microbial community. Very low and/or very high B/C ratios result in low microbial diversity, strong stochastic processes, and large, complex networks, leading to low pollutant removal load of treatment. A B/C ratio of around 0.5 was optimal for system stability and efficiency. Based on the results of this study, the authors propose using the B/C ratio as an indispensable index to assess system performance and to provide an indicator of an impending process upset before function deteriorates significantly. This study provides a specific measure that can be used to evaluate strategies for process optimization and operation of WWTPs.

8.
Nature ; 575(7783): 448-449, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31748718
9.
J Food Sci ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31750945

RESUMO

The influences of ultrasound-assisted, pharmacopeia, and supercritical fluid extraction methods on bioactive compounds and biological activities of propolis were evaluated. Results showed that propolis extracted by ultrasound-assisted method contained more phenolic compounds, and showed the highest total phenolic content (245.84 ± 6.41 mg GAE/g DW), total flavonoids content (198.82 ± 5.74 mg RE/g DW), and stronger in vitro antioxidant activity (DPPH·: 1.03 ± 0.04 mmol Trolox/g DW, ABTS+·: 2.19 ± 0.05 mmol Trolox/g DW, and FRAP: 1.48 ± 0.12 mmol FeSO4 /g DW) than those of pharmacopoeia and supercritical fluid methods. A total of 36 phenolic compounds were identified in propolis. Among them, quercetin, quercetin-3-methyl-ether, kaempferol, isorhamnetin, luteolin-methyl-ether, and quercetin-7-methyl-ether could only be found in ultrasound-assisted and pharmacopoeia methods. Moreover, the phenolic compounds had the similar metabolic pathways in rats and were mainly metabolized by sulfation and glucuronidation pathways. Additionally, ultrasonic-treated propolis have good in vivo antioxidant activity and could repair D-galactose-induced oxidative damage in rats. Therefore, ultrasound-assisted method could replace pharmacopeia method to be considered as bioactive compounds extraction from propolis, taking into consideration of yield, short extraction time, and high antioxidant activity.

10.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 376-380, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701727

RESUMO

OBJECTIVE: To investigate whether salidroside (Sal) plays a part in protecting myocardial cell through reducing the myocardial ischemia and the apoptosis pathway of both death receptors and mitochondria in acute exhausted rats. METHODS: Male SD rats were randomly divided into 4 groups (n=6): control group(Con), acute exhaustive swimming group (EE), low-dose and high-dose Sal pre-treatment exhaustive swimming group (SLE, SHE). Rats were treated with Sal solution (15 or 30 mg/(kg·d)) or 0.9%NaCl (3 ml/(kg·d)) by intraperitoneal injection for 15 d, respectively. The Con group did not carry out swimming training. The next day after the end of intraperitoneal administration, the rats in EE, SLE and SHE group were forced to swim until they were exhausted followed the standard of Thomas. After the end of exhaustive exercise, the rats were anesthetized and the blood samples and hearts were collected immediately. The myocardial ischemia and hypoxia area and myocardial apoptosis index (AI) were also observed. Serum ischemia modified albumin (IMA), cardiac troponin I (cTnI), brain natriuretic peptide(BNP) and myocardial cell Bcl-2-associated X protein (Bax), B-cell lymphoma-2 (Bcl-2) were determined. The expressions of myocardial TNF receptor superfamily member 6 (Fas), cytochrome C (Cyto-c), aspartate proteolytic enzyme-3(Caspase-3), aspartate proteolytic enzyme-8(Caspase-8), and aspartate proteolytic enzyme-9(Caspase-9) were detected. RESULTS: Compared with the Con group, the myocardial ischemia and hypoxia area in EE group was increased significantly. The serum levels of IMA, cTnI and BNP, AI and Bax levels and cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 protein expressions of EE group were also increased significantly (P<0.01), while the protein expression of Bcl-2 in cardiac tissues was decreased significantly (P<0.01). Compared with the EE group, the myocardial ischemia and hypoxia area, serum levels of IMA, cTnI and BNP, AI and Bax levels, and the protein expressions of cardiac Fas, Cyto-C, Caspase-3, Caspase-8 and Caspase-9 in Sal group were all decreased significantly(P<0.01). while the protein expression of cardiac Bcl-2 in Sal group were increased significantly (P<0.01). CONCLUSION: Sal plays a role in protecting myocardial cell through reducing the myocardial ischemia and inhibiting myocardial cell apoptosis in exhaustive exercise rats. The mechanism of reducing myocardial cell apoptosis may be related to inhibiting the expressions of Fas, Cyto-C, Caspase-3, Caspase-8, Caspase-9 and increasing the expression of Bcl-2.


Assuntos
Apoptose , Fadiga/fisiopatologia , Glucosídeos/farmacologia , Coração/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Fenóis/farmacologia , Animais , Biomarcadores/sangue , Feminino , Masculino , Miocárdio/citologia , Condicionamento Físico Animal , Ratos , Ratos Sprague-Dawley
11.
J Synchrotron Radiat ; 26(Pt 6): 2075-2080, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31721753

RESUMO

The upgrade of the laser pump time-resolved X-ray probes, namely time-resolved X-ray absorption spectroscopy (TR-XAS) and X-ray diffraction (TR-XRD), implemented at the Beijing Synchrotron Radiation Facility, is described. The improvements include a superbunch fill, a high-efficiency fluorescence collection, an efficient spatial overlap protocol and a new data-acquisition scheme. After upgrade, the adequate TR-XAS signal is now obtained in a 0.3 mM solution, compared with a 6 mM solution in our previous report. Furthermore, to extend application in photophysics, the TR-XAS probe is applied on SrCoO2.5 thin film. And for the first time, TR-XAS is combined with TR-XRD to simultaneously detect the kinetic trace of structural changes in thin film.

12.
CNS Neurosci Ther ; 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31729181

RESUMO

Aging and aging-related CNS diseases are associated with inflammatory status. As an efficient amplifier of immune responses, inflammasome is activated and played detrimental role in aging and aging-related CNS diseases. Macrophage and microglia display robust inflammasome activation in infectious and sterile inflammation. This review discussed the impact of inflammasome activation in microglia/macrophage on senescence "inflammaging" and aging-related CNS diseases. The preventive or therapeutic effects of targeting inflammasome on retarding aging process or tackling aging-related diseases are also discussed.

13.
HLA ; 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31696668

RESUMO

HLA-A*30:72 has one nucleotide change from HLA-A*30:01:01:01 where isoleucine (95) is changed to threonine.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31765797

RESUMO

BACKGROUND: Prepubertal vaginal bleeding is an uncommon occurrence in childhood. It can be a source of great concern for both pediatricians and family members. OBJECTIVE: This study characterizes the etiology, clinical features and outcomes of prepubescent vaginal bleeding and summarizes our experience. METHODS: The data of prepubertal patients who were hospitalized with vaginal discharge or bleeding treated in a provincial Grade III Level A Maternity and Children's Hospital from January 2012 to December 2018 were retrospectively reviewed. Patient age, bleeding duration, etiology, treatment and prognosis were recorded. Physical examinations and color Doppler ultrasonography were also performed. RESULTS: There were 158 patients aged from 1 month to 10 years (mean age 5.2 years). Bleeding duration ranged from 1 to 98 days, with an average of 13.3 days. Sixty patients were diagnosed with vaginal foreign bodies, 34 with vulvovaginitis, 34 with vulvar trauma, 13 with ovarian granulosa cell tumors, 8 with urethral mucosa prolapse, 5 with vaginal yolk sac tumors and 1 each with pituitary tumor, hypothyroidism, McCune-Albright syndrome and short-term intake of a large number of strawberries. All the children were treated according to their different disease etiologies. CONCLUSION: Prepubertal vaginal bleeding is caused by a variety of different conditions. In our study, the most common causes were vaginal foreign bodies, vulvovaginitis, trauma, vaginal malignant tumors and urethral mucosa prolapse. Careful medical histories and targeted examinations are needed. Vaginoscopy could be considered. Considering the different causes, different treatments should be administered to achieve a good prognosis.

16.
HLA ; 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31677233

RESUMO

HLA-B*52:01:24 has one synonymous nucleotide change from HLA-B*52:01:01:01 at nucleotide 384 (codon 104 Glycine).

17.
Neuropharmacology ; 162: 107836, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682854

RESUMO

Oxytocin (OT) and dopamine (DA) are two important elements that are closely related to mental and reward processes in the brain. OT controlled DA functional regulation contributes to various behaviours such as social reward, social cognition and emotion-related behaviours. Previous studies indicated that diminished dopaminergic transmission in the medial prefrontal cortex (mPFC) is correlated with the pathophysiology of depression. However, the interaction of OT and DA and their roles in antidepressant effects still require further exploration. Here, we investigated the antidepressant effect of OT through local mPFC administration, and further explored the underlying mechanisms that indicated that OT could strengthen dopaminergic synaptic transmission with OT receptor (OTR) activation dependent in the mPFC. Our results showed that local administration of OT in the mPFC exerts antidepressant (-like) effects in both naïve and social defeat stress (SDS) depressive animal model. Mechanism study suggested that OT enhances DA level with OTR activation dependent, and elevated mPFC DA levels might further enhance excitatory synaptic transmission by activating the D1/PKA/DARPP32 intracellular signalling pathway in the mPFC. Hence, our study revealed that the activation of OTR strengthens excitatory synaptic transmission via the potentiation of dopaminergic synaptic transmission, especially via D1R activation dependent, in the mPFC, which may be the underlying mechanism of antidepressant (-like) effects mediated by OT. With specifically activation of the D1/PKA/DAPRR32 signalling pathway, our results may augment the important role of OT in reward circuits in the central nervous system.

18.
Protein Cell ; 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31758528

RESUMO

Type VII secretion systems (T7SSs) are found in many disease related bacteria including Mycobacterium tuberculosis (Mtb). ESX-1 [early secreted antigen 6 kilodaltons (ESAT-6) system 1] is one of the five subtypes (ESX-1~5) of T7SSs in Mtb, where it delivers virulence factors into host macrophages during infection. However, little is known about the molecular details as to how this occurs. Here, we provide high-resolution crystal structures of the C-terminal ATPase3 domains of EccC subunits from four different Mtb T7SS subtypes. These structures adopt a classic RecA-like ɑ/ß fold with a conserved Mg-ATP binding site. The structure of EccCb1 in complex with the C-terminal peptide of EsxB identifies the location of substrate recognition site and shows how the specific signaling module "LxxxMxF" for Mtb ESX-1 binds to this site resulting in a translation of the bulge loop. A comparison of all the ATPase3 structures shows there are significant differences in the shape and composition of the signal recognition pockets across the family, suggesting that distinct signaling sequences of substrates are required to be specifically recognized by different T7SSs. A hexameric model of the EccC-ATPase3 is proposed and shows the recognition pocket is located near the central substrate translocation channel. The diameter of the channel is ~25-Å, with a size that would allow helix-bundle shaped substrate proteins to bind and pass through. Thus, our work provides new molecular insights into substrate recognition for Mtb T7SS subtypes and also a possible transportation mechanism for substrate and/or virulence factor secretion.

19.
Curr Neurovasc Res ; 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31702493

RESUMO

BACKGROUND: Function of microRNA-542-3p (miR-542-3p) in rat epilepsy is still unclear. METHODS: The levels of miR-542-3p and toll-like receptor 4 (TLR4) were determined through quantitative real-time PCR. The protein levels were examined via western blot analysis. The relationship between miR-542-3p and TLR4 was confirmed through luciferase assay. Pathological changes were analyzed via Hematoxylin-eosin (HE) and Nissl staining. RESULTS: The rats and hippocampal cells were treated with kainic acid (KA) in vivo and in vitro. miR-542-3p was low in KA-treated rats, hippocampal cells and cerebrospinal fluid of patients with epilepsy. Further functional analysis showed that miR-542-3p overexpression inhibited KA-induced average seizure frequency, damage of hippocampal neuron and cell apoptosis, leading to alleviation of the brain injury in epilepsy rats. miR-542-3p was determined to downregulate TLR4 expression. The relationship between miR-542-3p and TLR4 was confirmed. TLR4 knockdown reduced KA-induced nuclear factor-kappa B p65 (NF-κB p65), multidrug resistance 1 (MDR1), P-glycoprotein (P-gp) and apoptosis-associated protein levels. Further, for NF-κB p65, MDR1, P-gp and apoptosis-associated protein levels detection, miR-542-3p mimic showed a suppressive effect on these KA-induced protein levels, whereas TLR4 overexpression ameliorated the miR-542-3p-induced these protein levels in KA-treated epilepsy rats. CONCLUSION: We identified that miR-542-3p attenuated seizure-induced brain injury and the expression of P-gp in epilepsy rats through inhibiting TLR4/NF-κB signaling pathway, which might contribute to improve epilepsy therapy.

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