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1.
Environ Pollut ; 260: 113984, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32041019

RESUMO

1-nitropyrene (1-NP) is a key component of diesel exhaust-sourced fine particulate matter (PM2.5). Our recent study demonstrated that gestational 1-NP exposure caused placental proliferation inhibition and fetal intrauterine growth restriction (IUGR). This study aimed to investigate the role of genotoxic stress on 1-NP-induced placental proliferation inhibition and fetal IUGR. Human trophoblasts were exposed to 1-NP (10 µM). Growth index was reduced and PCNA was downregulated in 1-NP-exposed placental trophoblasts. More than 90% of 1-NP-exposed trophoblasts were arrested in either G0/G1 or G2/M phases. CDK1 and cyclin B, two G2/M cycle-related proteins, and CDK2, a G0/G1 cycle-related protein, were reduced in 1-NP-exposed trophoblasts. Phosphorylated Rb, a downstream molecule of CDK2, was inhibited in 1-NP-exposed trophoblasts. Moreover, DNA double-strand break was observed and γ-H2AX, another indicator of DNA double-strand break, was upregulated in 1-NP-exposed trophoblasts. Phosphorylated ATM, a key molecule of genotoxic stress, and its downstream molecule Chk2 were elevated. By contrast, Cdc25A, a downstream target of Chk2, was reduced in 1-NP-exposed trophoblasts. Phenyl-N-t-butylnitrone (PBN), a free radical scavenger, inhibited 1-NP-induced genotoxic stress and trophoblast cycle arrest. Animal experiment showed that N-acetylcysteine (NAC), an antioxidant, rescued 1-NP-induced placental proliferation inhibition and fetal IUGR in mice. These results provide evidence that reactive oxygen species (ROS)-mediated cellular genotoxic stress partially contributes to 1-NP-induced placental proliferation inhibition and fetal IUGR.

2.
Sci Total Environ ; 703: 134699, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31726297

RESUMO

Microplastics, whether originating directly from industrial and household products or from the degradation of larger plastics, are currently of intense global concern. These particles are present in aquatic environments in high concentrations and may adversely affect aquatic organisms. An additional concern is the ability of microplastics to adsorb inorganic and organic pollutants and subsequently liberate them into marine and freshwater systems. In this review, we report on the occurrence and abundance of microplastics in the global aquatic environment. We then consider the accumulation (uptake, distribution, and elimination) of microplastics in aquatic organisms and the important factors that lead to bioaccumulation. The effects of microplastics on aquatic organisms of different trophic levels are also discussed. Several studies have shown that the size, shape, and surface physicochemical characteristics of microplastics are essential determinants of their biological effects. Finally, we examine the combined effects of microplastics and other pollutants, including persistent organic pollutants and heavy metals. Our review concludes by suggesting future lines of research based on the remaining knowledge gaps in microplastic research.

3.
Cancer Sci ; 111(1): 59-71, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31729097

RESUMO

Low vitamin D status is associated with progression in patients with renal cell carcinoma (RCC). The present study found that vimentin, a mesenchymal marker, was accordingly upregulated, and E-cadherin, an epithelial marker, was downregulated in RCC patients with low vitamin D status. Thus, we investigated the effects of calcitriol or vitamin D3, an active form of vitamin D, on epithelial-mesenchymal transition (EMT) in RCC cells. RCC cells were treated by two models. In model 1, three RCC cell lines, ACHN, 786-O and CAKI-2, were incubated with either LPS (2.0 µg/mL) or transforming growth factor (TGF)-ß1 (10 ng/mL) in the presence or absence of calcitriol (200 nmol/L). In model 2, two RCC cell lines, ACHN and CAKI-2, were incubated with calcitriol (200 nmol/L) only. Calcitriol inhibited migration and invasion not only in TGF-ß1-stimulated but also in TGF-ß1-unstimulated RCC cells. Moreover, calcitriol suppressed E-cadherin downregulation and vimentin upregulation not only in TGF-ß1-stimulated but also in TGF-ß1-unstimulated ACHN and CAKI-2 cells. Calcitriol attenuated LPS-induced upregulation of MMP-2, MMP-7, MMP-9, MMP-26 and urokinase-type plasminogen activator (u-PA) in ACHN cells. In addition, calcitriol blocked TGF-ß1-induced nuclear translocation of ZEB1, Snail and Twist1 in ACHN and CAKI-2 cells. Mechanistically, calcitriol suppressed EMT through different signaling pathways: (i) calcitriol suppressed Smad2/3 phosphorylation by reinforcing physical interaction between vitamin D receptor (VDR) and Smad3 in TGF-ß1-stimulated RCC cells; (ii) calcitriol inhibited signal transducer and activator of transcription (STAT)3 activation in LPS-stimulated RCC cells; (iii) calcitriol inhibited ß-catenin/TCF-4 activation by promoting integration of VDR with ß-catenin in TGF-ß1-unstimulated RCC cells. Taken together, calcitriol inhibits migration and invasion of RCC cells partially by suppressing Smad2/3-, STAT3- and ß-catenin-mediated EMT.


Assuntos
Calcitriol/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Adulto , Idoso , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Renais/metabolismo , Masculino , Metaloendopeptidases/metabolismo , Pessoa de Meia-Idade , Fator de Transcrição STAT3/metabolismo , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , beta Catenina/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-31708873

RESUMO

The G protein-coupled estrogen receptor (GPER) is a seven-transmembrane-domain receptor that mediates non-genomic estrogen related signaling. After ligand activation, GPER triggers multiple downstream pathways that exert diverse biological effects on the regulation of cell growth, migration and programmed cell death in a variety of tissues. A significant correlation between GPER and the progression of multiple cancers has likewise been reported. Therefore, a better understanding of the role GPER plays in cancer biology may lead to the identification of novel therapeutic targets, especially among estrogen-related cancers. Here, we review cell signaling and detail the functions of GPER in malignancies.

5.
Sci Rep ; 9(1): 16719, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31723229

RESUMO

Low vitamin D status is associated with an increased risk of renal cell carcinoma (RCC). This study investigated the association of vitamin D status with serum C-reactive protein (CRP) and adhesion molecules among RCC patients. Fifty newly diagnosed RCC patients and 100 age- and sex-matched controls were recruited. As expected, serum 25(OH)D level was lower in RCC patients than in controls. By contrast, serum levels of CRP, an inflammatory molecule, and ICAM, LAMA4 and EpCAM, three adhesion molecules, were higher in RCC patients than in controls. All RCC patients were divided into two groups: H-VitD (>20 ng/ml) or L-VitD (<20 ng/ml). Interestingly, the levels of serum CRP and all adhesion molecules were higher in RCC patients with L-VitD than those with H-VitD. Nuclear vitamin D receptor (VDR) was downregulated and nuclear factor kappa B (NF-κB) was activated in cancerous tissues. The in vitro experiments found that VitD3 suppressed NF-κB activation and adhesion molecules in RCC cells. Moreover, VitD3 suppressed NF-κB through reinforcing physical interaction between VDR and NF-κB p65 subunit in RCC cells. These results provide a mechanistic explanation for the association among low vitamin D status, local inflammation and increased expression of adhesion molecules among RCC patients.

6.
ACS Omega ; 4(5): 9129-9134, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31460001

RESUMO

Molecular conformation plays an important role in tuning the packing modes of organic optoelectronic materials to achieve enhanced and/or balanced charge transport. Here, we introduce the noncovalent intramolecular interactions to the host materials of phosphorescent organic light-emitting diodes (PhOLEDs). Different numbers and/or positions of intramolecular CH···N noncovalent interactions were constructed by using different N-heterocycles of pyridine, pyrimidine, and pyrazine as acceptor units and carbazole as the donor unit in a donor-acceptor-donor (D-A-D) motif. Thus, designed D-A-D molecules were synthesized facilely through a one-step Ullmann reaction in high yields, showing varied intramolecular interactions to regulate the molecular conformation significantly. Impressively, owing to the quasi-parallel molecular conformation, which is beneficial for forming facile transporting channels of both holes and electrons, the newly designed host material of 9,9'-(pyridine-2,5-diyl)bis(9H-carbazole) exhibits good device performance of blue PhOLEDs with current, power, and external quantum efficiencies up to 33.0 cd A-1, 32.1 lm W-1, and 16.3%, respectively. This work highlights the significant importance of the noncovalent interactions in designing advanced organic semiconductors for high-performance optoelectronic devices.

7.
J Immunol ; 203(5): 1198-1207, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31315888

RESUMO

It is increasingly recognized that excessive glucocorticoids induce fetal intrauterine growth restriction (IUGR). Placental 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), a glucocorticoid-catalyzing enzyme, prevents active glucocorticoids from maternal circulation into the fetus, thus protecting against IUGR. Previous studies demonstrated gestational LPS exposure caused fetal IUGR. The aim of the current study was to investigate the effects of LPS on 11ß-HSD2 in mice placentas and human placental trophoblasts. Pregnant ICR(CD-1) mice were i.p. injected with LPS (200 µg/kg) on gestational day 16. As expected, gestational LPS exposure downregulated 11ß-HSD2 in mice placentas. In vitro, LPS downregulated 11ß-HSD2 in human placental trophoblasts. Additional experiment showed that LPS, which activated NF-κB, suppressed rosiglitazone-induced activation of peroxisome proliferator-activated receptor-γ (PPARγ) in mice placentas and human placental trophoblasts. Moreover, NF-κB p65 knockdown and specific NF-κB inhibitor attenuated LPS-induced suppression of PPARγ nuclear translocation in human placental trophoblasts. In addition, NF-κB p65 knockdown attenuated LPS-induced downregulation of 11ß-HSD2 in human placental trophoblasts. Mechanically, LPS promoted physical interaction between NF-κB p65 and PPARγ in the cytoplasm and nucleus of placental trophoblasts. Finally, pretreatment with rosiglitazone, a PPARγ agonist, partially alleviated LPS-induced reduction of fetal weight and crown-rump length. Taken together, these results suggest that LPS downregulates 11ß-HSD2 through suppressing PPARγ in placental trophoblasts. Placental 11ß-HSD2 downregulation may contribute partially to LPS-induced fetal IUGR.

8.
Steroids ; 150: 108445, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31295461

RESUMO

Low vitamin D status has been associated with increased risks of renal cell carcinoma (RCC). This study aimed to analyze the link between low vitamin D status and interleukin (IL)-6/STAT3 hyper-activation in clear cell RCC (ccRCC) patients. Forty-three newly diagnosed ccRCC patients and 86 age- and sex-matched controls were recruited. The association between low vitamin D status and IL-6/STAT3 hyper-activation was analyzed. Proliferation makersand STAT3 signal were evaluated. As expected, serum IL-6 level was higher in ccRCC patients than in controls. Moreover, serum IL-6 level was reversely correlated with serum 25(OH)D in ccRCC patients but not in controls. In addition, STAT3 signaling was hyper-activated in cancerous tissue. CcRCC patients were divided into three groups according to serum 25(OH)D level: vitamin D sufficiency (VitD-S, ≥30 ng/ml), vitamin D insufficiency (VitD-I, ≥20 and <30 ng/ml) or vitamin D deficiency (VitD-D, <20 ng/ml). Serum IL-6 was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. Cancerous pSTAT3 level was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The number of pSTAT3+ nuclei in cancerous tissue was more in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The expressions of cancerous PCNA, cyclin D1 and Ki-67, three markers of proliferation, were higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The in vitro experiments showed that active vitamin D3 inhibited LPS-induced STAT3 phosphorylation in ACHN cells. Our results provide evidence that low vitamin D status is correlated with hyper-activation of cancerous IL-6/STAT3 and proliferation in ccRCC patients.

9.
Chem Sci ; 10(19): 5031-5038, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31183053

RESUMO

Invoking efficient afterglow in metal-free organic molecules represents an important material advancement. However, organic afterglow suffers from low intensity and efficiency and generally needs to be excited by UV light owing to its spin-forbidden phosphorescent nature that essentially requires facile intersystem crossing (ISC). Here, we propose a strategy to bypass the traditional ISC through facilitating singlet-triplet transition to directly populate triplet excited states from the ground state by combining synergetic effects of both heavy/hetero-atom incorporation and aromatic aggregation. Verified by systematic experimental and computational investigations, this unique singlet-to-triplet absorption results in a much improved organic afterglow quantum efficiency up to 9.5% with a prolonged lifetime of 0.25 s under visible-light irradiation. Fundamentally, this work illustrates for the first time the great potential of the direct population method to red-shift the excitation wavelength and improve the afterglow efficiency, offering important clues for the development of triplet-state involved organic optoelectronic technologies.

10.
Environ Sci Technol ; 53(13): 7803-7811, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31244069

RESUMO

Rapid developments in nanotechnology have led to the release of substantial amounts of nanoparticles (NPs) into aquatic environments, where many types of biotic particles are present and could potentially interact with the NPs. Nevertheless, how biotic particles may affect the bioaccumulation and toxicity of NPs remains largely unknown. In the present study, we investigated the effects of the green alga Chlamydomonas reinhardtii on the accumulation kinetics (uptake, assimilation, efflux) and toxicity of polyacrylate-coated hematite NPs (HemNPs), using Daphnia magna as the test organism. As a biotic particle and daphnid food, C. reinhardtii reduced the accumulation and toxicity of HemNPs in D. magna. The HemNPs were well-dispersed with little adsorption to the alga. Their decreased accumulation could thus be partly explained by their low trophic transfer from the alga to the daphnid and by the inductive effects of the alga on HemNP efflux. However, the main cause was the direct inhibition of HemNP uptake from the water phase as a result of the reduced water-filtration activity of D. magna in the presence of C. reinhardtii. Overall, in bioaccumulation studies, the inhibitory effects of biotic particles on NP uptake from the water phase should be paid attention.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Animais , Daphnia , Compostos Férricos , Água
11.
Oxid Med Cell Longev ; 2019: 1897316, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31019650

RESUMO

Background: Cellular stress is involved in ischemia/reperfusion- (I/R-) induced acute kidney injury (AKI). This study is aimed at investigating the effects of pretreatment with cholecalciferol on renal oxidative stress and endoplasmic reticulum (ER) stress during I/R-induced AKI. Methods: I/R-induced AKI was established by cross-clamping renal pedicles for 90 minutes and then reperfusion. In the Chol + I/R group, mice were orally administered with three doses of cholecalciferol (25 µg/kg) at 1, 24, and 48 h before ischemia. Renal cellular stress and kidney injury were measured at different time points after reperfusion. Results: I/R-induced AKI was alleviated in mice pretreated with cholecalciferol. In addition, I/R-induced renal cell apoptosis, as determined by TUNEL, was suppressed by cholecalciferol. Additional experiment showed that I/R-induced upregulation of renal GRP78 and CHOP was inhibited by cholecalciferol. I/R-induced renal IRE1α and eIF2α phosphorylation was attenuated by cholecalciferol. Moreover, I/R-induced renal GSH depletion, lipid peroxidation, and protein nitration were blocked in mice pretreated with cholecalciferol. I/R-induced upregulation of renal NADPH oxidases, such as p47phox, gp91phox, and nox4, was inhibited by cholecalciferol. I/R-induced upregulation of heme oxygenase- (HO-) 1, gshpx and gshrd, was attenuated in mice pretreated with cholecalciferol. Conclusions: Pretreatment with cholecalciferol protects against I/R-induced AKI partially through suppressing renal cellular stress response.


Assuntos
Lesão Renal Aguda/etiologia , Lesão Renal Aguda/patologia , Colecalciferol/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Rim/patologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/complicações , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Glutationa/metabolismo , Rim/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Camundongos Endogâmicos ICR , NADPH Oxidases/metabolismo , Receptores de Calcitriol/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
12.
Brain Behav ; 9(4): e01251, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30859753

RESUMO

BACKGROUND: Tissue plasminogen activator (t-PA) is an effective therapy for acute ischemic stroke, but some patients still have poor clinical outcome. In this study, we investigated clinical characteristics of stroke patients and determined predictors for poor clinical outcome in response to t-PA treatment. METHODS: Clinical data from 247 patients were retrospectively reviewed. Clinical parameters that were associated with survival of patients were analyzed. Areas under receiver operating characteristic curves (ROC) were used to determine the feasibility of using various combinations of the clinical parameters to predict poor clinical response. The clinical outcome was defined according to the changes in Modified Rankin Scale. RESULTS: Overall, 145 patients had improved/complete recovery, 73 had no change, and 29 had worsening conditions or died during the in-clinic period. A univariate analysis showed that baseline characteristics including age, CRP, blood glucose level, systolic blood pressure, and admission NIHSS were significantly different (p < 0.05) among patients with different clinical outcome. A further multivariate analysis was then performed. Variables associated with poor clinical outcome (worsening/death) (p < 0.1) were included in the logistic regression model. Four parameters were retained in the model: Age, CRP, Blood glucose level, and Systolic blood pressure (ACBS). To allow a convenient usage of the ACBS classifier, the parameters were put into a scoring system, and the score at 7.7 was chosen as a cut-off. The ROC curve of this ACBS classifier has an area under the curve (AUC) of 0.7788, higher than other individual parameters. The ACBS classifier provided enhanced sensitivity of 69.2% and specificity of 74.3%. CONCLUSION: The ACBS classifier provided a satisfactory power in estimating the patients' clinical outcome. After further validating, the classifier may provide important information to clinicians for making clinical decisions.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terapia Trombolítica , Resultado do Tratamento
13.
Int Immunopharmacol ; 69: 235-244, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30738993

RESUMO

Several epidemiological reports demonstrated that vitamin D deficiency elevated risk of preterm delivery. We investigate the effects of oral cholecalciferol (VD3) supplementation on lipopolysaccharide (LPS)-induced preterm delivery. Pregnant mice were randomly assigned to either oral VD3 (25 µg/kg) or corn oil once daily from gestational day (GD)13 to GD15, and were intraperitoneally injected with either LPS (200 µg/kg) or normal saline on GD15. As expected, LPS was effective in inducing preterm delivery and fetal death. LPS-induced preterm delivery and fetal death were alleviated in VD3-pretreated mice. LPS-induced down-regulation of genes for placental progesterone biosynthetic enzymes was blocked in VD3-pretreated mice. LPS-induced reduction of serum progesterone was correspondingly attenuated by VD3. Although oral VD3 had no effect on estradiol production, it attenuated LPS-induced up-regulation of placental ERß in mice. LPS-induced placental COX-2 up-regulation and serum PGF2α elevation were alleviated in VD3-pretreated mice. Additionally, LPS-evoked elevations of the placental Tnfα, Il1ß, Mcp1 and Mip2 mRNAs were attenuated by VD3. VD3 promoted placental vitamin D receptor nuclear translocation and simultaneously alleviated LPS-induced nuclear translocation of NF-κB p65 and p50 subunits. These results provide evidence that oral VD3 supplementation alleviates LPS-induced preterm delivery and fetal demise partially through regulating placental steroid hormones and prostaglandins.


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Placenta/metabolismo , Nascimento Prematuro/dietoterapia , Receptores de Calcitriol/metabolismo , Administração Oral , Animais , Estradiol/metabolismo , Feminino , Humanos , Inflamação , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos ICR , Gravidez , Progesterona/metabolismo , Prostaglandinas/metabolismo
14.
Sci Total Environ ; 653: 1293-1300, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30759569

RESUMO

Chemical oxidation and microbial degradation are promising treatments to remediate soils contaminated with persistent organic pollutants. Moderate pre-oxidation is able to enhance the subsequent bioremediation of organic pollutants in soil. In this study, the effects of pre-oxidation on the subsequent biodegradation of benzo[a]pyrene (BaP) were evaluated. The tested oxidants included potassium permanganate (PP) and iron-activated sodium persulfate (PS) at the concentration of 1-40 mmol L-1. The results showed that 20 mmol L-1 PS and 10 mmol L-1 PP treatments had the highest degradation efficiency of BaP in soil, up to 98.7% and 84.2%, without inhibiting subsequent microbial degradation. 10-20 mmol L-1 of the two oxidants significantly promoted viability of microbial community. Especially, PS facilitated the occurrence of more PAHs-degrading microorganisms. The expression of PAH-degradation gene in PS treatment was significantly higher than that in PP treatment (P < 0.05), leading to 12.0-18.4% higher degradation efficiencies of BaP. In general, proper oxidants of moderate dosages were able to promote microbial bioremediation of persistent organic pollutants in soil.


Assuntos
Benzo(a)pireno/metabolismo , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/metabolismo , Oxirredução , Permanganato de Potássio/química , Compostos de Sódio/química , Microbiologia do Solo , Sulfatos/química
15.
J Cell Physiol ; 234(8): 13318-13331, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30633347

RESUMO

We examined ultrastructure protective phenomena and mechanisms of slow and fast muscles in hibernating Daurian ground squirrels (Spermophilus dauricus). Some degenerative changes such as slightly decreased sarcomere length and vacuolization occurred in hibernation, but periaxonal capsular borders in intrafusal fibers remained distinct and the arrangement of extrafusal fibers and Z-lines unscathed. In soleus samples, the number of glycogenosomes more than tripled during hibernation. The expression of phosphorylated glycogen synthase remained unaltered while that of glycogen phosphorylase decreased during hibernation. The number of extensor digitorum longus glycogenosomes decreased and the expression of phosphorylated glycogen synthase decreased, while glycogen phosphorylase expression remained unaltered. The nuclei number remained unchanged. Kinesin and desmin, preventors of nuclear loss and damage, were maintained or just slightly reduced in hibernation. The single-fiber mitochondrial concentration and sub-sarcolemmal mitochondrial number increased in both muscle types. The expression of vimentin, which anchors mitochondria and maintains Z-line integrity, was increased during and after hibernation. Also, dynamin-related protein 1, mitochondrial fission factor, and adenosine triphosphate synthase were elevated in both muscle types. These findings confirm a remarkable ultrastructure preservation and show an unexpected increase in mitochondrial capacity in hibernating squirrels.

16.
Nanoscale ; 10(48): 23087-23102, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30511715

RESUMO

Steady state Raman spectroscopy is the most widely used opto-thermal technique for measuring a 2D atomic-layer material's thermal conductivity. It requires the calibration of temperature coefficients of Raman properties and measurement/calculation of the absolution laser absorption in 2D materials. Such a requirement is very laborious and introduces very large measurement errors (of the order of 100%) and hinders gaining a precise and deep understanding of phonon-structure interactions in 2D materials. In this work, a novel nanosecond energy transport state resolved Raman (ns ET-Raman) technique is developed to resolve these critical issues and achieve unprecedented measurement precision, accuracy and ease of implementation. In ns ET-Raman, two energy transport states are constructed: steady state and nanosecond thermal transport and Raman probing. The ratio of the temperature rise under the two states eliminates the need for Raman temperature calibration and laser absorption evaluation. Four suspended MoS2 (45-115 nm thick) and four suspended MoSe2 (45-140 nm thick) samples are measured and compared using ns ET-Raman. With the increase of the sample thickness, the measured thermal conductivity increases from 40.0 ± 2.2 to 74.3 ± 3.2 W m-1 K-1 for MoS2, and from 11.1 ± 0.4 to 20.3 ± 0.9 W m-1 K-1 for MoSe2. This is attributed to the decreased significance of surface phonon scattering in thicker samples. The ns ET-Raman features the most advanced capability to measure the thermal conductivity of 2D materials and will find broad applications in studying low-dimensional materials.

17.
Shanghai Kou Qiang Yi Xue ; 27(4): 401-406, 2018 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-30483709

RESUMO

PURPOSE: To evaluate the clinical effect of short implants in atrophic posterior region. METHODS: A total of 38 Bicon short implants (≤8 mm) were placed in 30 patients with 3-10 mm of bone height in the posterior region from January to December 2012. The follow-up period was 4 years, radiographic, clinical examination(improved plaque index, improved bleeding index, probing depth)were conducted and patient satisfactions were investigated with Oral Health Impact Profile (OHIP-I). Statistical analysis was performed using SPSS17.0 software package. RESULES: Implant survival rate of short implants was 100% and implant success rate was 94.7%. The mean peri-implant bone resorption value was (0.25±0.65) mm,the change of mesial and distal marginal bone was (-0.23±0.74) mm and (-0.27±0.59) mm, respectively. Crown to implant ratio (C/I)= 1.77±0.34, the implants were divided into 3 groups according to C/I≤1,12,there was no significant difference in marginal bone changes and no correlation between C/I and bone resorption. Through clinical examination,improved plaque index was 1.08±0.88,improved bleeding index was 1.11±0.83 and the average probing depth was (3.08±1.19) mm. OHIP-I score was 2.66±0.88, there was significant difference compared with preoperative OHIP-I score. CONCLUSIONS: Short implants are feasible and the success rate is high in the posterior region with insufficient bone height. The soft tissue around the short implants is in good health.While avoiding complex surgical procedures, reducing trauma, shortening the duration of treatment,short implants have a high degree of acceptance and the patient satisfactions are excellent.At the same time, regular preventive maintenance is important to maintain the long-term stability of implant dentures.


Assuntos
Coroas , Implantação Dentária , Implantes Dentários , Prótese Dentária Fixada por Implante , Perda do Osso Alveolar , Implantação Dentária Endo-Óssea , Planejamento de Prótese Dentária , Seguimentos , Humanos , Resultado do Tratamento
18.
Org Lett ; 20(20): 6376-6379, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30295498

RESUMO

Two new building blocks of perylene-embedded benzoazoles containing both rigid 2D-conjugated aromatic rings and flexible branched alkyl chains were designed and facilely synthesized in high yields for organic solar cells (OSCs). With a typical acceptor of diketopyrrolopyrrole, small molecular OSC donors constructed in an acceptor-fused donor-acceptor motif exhibit excellent solubility, stability, and light absorption with tunable frontier orbitals, leading to a power conversion efficiency of up to 2.88% in preliminary OSCs.

19.
Eur J Pharmacol ; 838: 60-68, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30196109

RESUMO

It is increasingly recognized that farnesoid X receptor (FXR) has anti-inflammatory and antioxidant activities. The present study investigated the effects of obeticholic acid (OCA), a novel synthetic FXR agonist, on renal inflammation and oxidative stress in a model of sepsis-induced acute kidney injury. All mice except controls were intraperitoneally injected with lipopolysaccharide (LPS, 2.0 mg/kg). In the OCA + LPS group, mice were orally pretreated with three doses of OCA (5 mg/kg) at 48, 24 and 1 h before LPS injection. Interestingly, OCA pretreatment alleviated LPS-induced renal dysfunction and pathological damage. Moreover, OCA pretreatment repressed renal inflammatory cytokines and chemokines during LPS-induced acute kidney injury. In addition, OCA blocked nuclear translocation of nuclear factor kappa B (NF-κB) p65 and p50 subunits in tubular epithelial cells of renal cortex. Additional experiment showed that OCA pretreatment attenuated LPS-induced renal glutathione depletion, lipid peroxidation and protein nitration. Moreover, OCA pretreatment inhibited the upregulation of renal NADPH oxidase and inos genes during LPS-induced acute kidney injury. In conclusion, OCA pretreatment protects against sepsis-induced acute kidney injury through inhibiting renal inflammation and oxidative stress. These results provide evidence for roles of FXR as an important regulator of inflammation and oxidative stress in the kidney.


Assuntos
Lesão Renal Aguda/tratamento farmacológico , Ácido Quenodesoxicólico/análogos & derivados , Nefrite/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/agonistas , Lesão Renal Aguda/imunologia , Lesão Renal Aguda/patologia , Administração Oral , Animais , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico , Modelos Animais de Doenças , Humanos , Rim/efeitos dos fármacos , Rim/patologia , Lipopolissacarídeos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nefrite/imunologia , Nefrite/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo
20.
Health Policy ; 122(12): 1356-1363, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30249447

RESUMO

OBJECTIVE: To explore the factors that influence trust among the integrated healthcare service provider network in the context of seeking combined health and care services in the UK. DATA SOURCES/STUDY SETTING: Primary data were collected from three regional integrated care service provider networks from March 2016 to October 2017. STUDY DESIGN: Explorative qualitative study and inductive methods from emerging findings. DATA COLLECTION/EXTRACTION METHODS: We conducted qualitative semi-structured interviews in three care networks and collected organizational documents from local integration boards from 2016 to 2017. Thematic analysis was performed in three large care networks with hospital staff, local councils, integration boards, and community and voluntary organizations under the NHS England Better Care Fund. PRINCIPAL FINDINGS: Our findings reveal that trust among integrated care service provider networks is influenced by the following factors on various asymmetries: 1) recognition and knowledge asymmetries among care service partners of each other's skills, expertise and capabilities; 2) capacity and financial imbalances within the network; and 3) organizational differences in management, culture and attitudes toward change. CONCLUSION: There is a need to improve competence recognition and capacity imbalances and to foster open minds toward change within networks to build trust to overcome divisions and facilitate integrated services among health and care organizations.


Assuntos
Comportamento Cooperativo , Prestação Integrada de Cuidados de Saúde/organização & administração , Confiança , Inglaterra , Humanos , Entrevistas como Assunto , Cultura Organizacional , Pesquisa Qualitativa
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