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1.
J Chem Theory Comput ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33593057

RESUMO

Although quantum mechanical/molecular mechanics (QM/MM) methods are now routinely applied to the studies of chemical reactions in condensed phases and enzymatic reactions, they may experience technical difficulties when the reactive region is varying over time. For instance, when the solvent molecules are directly participating in the reaction, the exchange of water molecules between the QM and MM regions may occur on a time scale comparable to the reaction time. To cope with this situation, several adaptive QM/MM schemes have been proposed. However, these methods either add significantly to the computational cost or introduce artificial restraints to the system. In this work, we developed a novel adaptive QM/MM scheme and applied it to the study of a nucleophilic addition reaction. In this scheme, the configuration sampling was performed with a small QM region (without solvent molecules), and the thermodynamic properties under another potential energy function with a larger QM region (with a certain number of solvent molecules and/or different levels of QM theory) are computed via extrapolation using the reference-potential method. Our simulation results show that this adaptive QM/MM scheme is numerically stable, at least for the case studied in this work. Furthermore, this method also offers an inexpensive way to examine the convergence of the QM/MM calculation with respect to the size of the QM region.

2.
Cell Death Dis ; 11(11): 971, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33184264

RESUMO

Vagus nerve stimulation (VNS) restores autonomic balance, suppresses inflammation action and minimizes cardiomyocyte injury. However, little knowledge is known about the VNS' role in cardiomyocyte phenotype, sarcomere organization, and energy metabolism of infarcted hearts. VNS in vivo and acetylcholine (ACh) in vitro optimized the levels of α/ß-MHC and α-Actinin positive sarcomere organization in cardiomyocytes while reducing F-actin assembly of cardiomyocytes. Consistently, ACh improved glucose uptake while decreasing lipid deposition in myocytes, correlating both with the increase of Glut4 and CPT1α and the decrease of PDK4 in infarcted hearts in vivo and myocytes in vitro, attributing to improvement in both glycolysis by VEGF-A and lipid uptake by VEGF-B in response to Ach. This led to increased ATP levels accompanied by the repaired mitochondrial function and the decreased oxygen consumption. Functionally, VNS improved the left ventricular performance. In contrast, ACh-m/nAChR inhibitor or knockdown of VEGF-A/B by shRNA powerfully abrogated these effects mediated by VNS. On mechanism, ACh decreased the levels of nuclear translocation of FoxO3A in myocytes due to phosphorylation of FoxO3A by activating AKT. FoxO3A overexpression or knockdown could reverse the specific effects of ACh on the expression of VEGF-A/B, α/ß-MHC, Glut4, and CPT1α, sarcomere organization, glucose uptake and ATP production. Taken together, VNS optimized cardiomyocytes sarcomere organization and energy metabolism to improve heart function of the infarcted heart during the process of delaying and/or blocking the switch from compensated hypertrophy to decompensated heart failure, which were associated with activation of both P13K/AKT-FoxO3A-VEGF-A/B signaling cascade.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33118924

RESUMO

A Gram-stain-negative, strictly aerobic, non-motile, orange-coloured bacterium, designated YR1-1T, was isolated from a soil sample collected from the Yellow River Delta wetlands (PR China). Growth was observed at a salinity of 1.0-15.0 % NaCl, 4-45 °C and pH 6.0-9.0. The results of phylogenetic analysis based on the 16S rRNA gene sequences indicated that YR1-1T represented a member of the genus Psychroflexus, with the highest sequence similarity to Psychroflexus sediminis YIM-C238T (97.9 %), followed by Psychroflexus aestuariivivens (97.1 %) and Psychroflexus torquis (96.4 %). The average nucleotide identity and digital DNA-DNA hybridization values between YR1-1T and other closely related type strains of species of the genus Psychroflexus were 68.7-86.3% and 17.8-30.9 %. The genome of the strain was 2 899 374 bp in length with 39.8 % DNA G+C content. The predominant fatty acids (>10 %) were iso-C15 : 0 and anteiso-C15 : 0. The major respiratory quinone was menaquinone-6 (MK-6) and the major polar lipids were phosphatidylethanolamine, phospholipid, diphosphatidylglycerol, two unidentified aminolipids and four unidentified lipids. The combined genotypic and phenotypic data indicate that YR1-1T represents a novel species within the genus Psychroflexus, for which the name Psychroflexus aurantiacus sp. nov., is proposed. The type strain is YR1-1T (=KCTC 72794T=CGMCC 1.17458T).

4.
J Chem Theory Comput ; 16(11): 6814-6822, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32975951

RESUMO

Calculations of the free energy profile, also known as potential of mean force (PMF), along a chosen collective variable (CV) are now routinely applied in the studies of chemical processes, such as enzymatic reactions and chemical reactions in condensed phases. However, if the ab initio quantum mechanical/molecular mechanics (QM/MM) level of accuracy is required for the PMF, it can be formidably demanding even with the most advanced enhanced sampling methods, such as umbrella sampling. To ameliorate this difficulty, we developed a novel method for the computation of the free energy profile based on the reference-potential method recently, in which a low-level reference Hamiltonian is employed for phase space sampling and the free energy profile can be corrected to the level of interest (the target Hamiltonian) by energy reweighting in a nonparametric way. However, when the reference Hamiltonian is very different from the target Hamiltonian, the calculated ensemble averages, including the PMF, often suffer from numerical instability, which mainly comes from the overestimation of the density-of-states (DoS) in the low-energy region. Stochastic samplings of these low-energy configurations are rare events, and some low-energy conformations may get oversampled in simulations of a finite length. In this work, an assumption of Gaussian distribution is applied to the DoS in each CV bin, and the weight of each configuration is rescaled according to the accumulated DoS. The results show that this smoothing process can remarkably reduce the ruggedness of the PMF and increase the reliability of the reference-potential method.

5.
Int J Syst Evol Microbiol ; 70(10): 5373-5381, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886596

RESUMO

A Gram-stain-negative, strictly aerobic, non-motile, rod-shaped bacterium, designated CWB-1T, was isolated from a haloalkaline lake sediment sample collected from the bottom of Chaiwopu Lake, Urumchi, Xinjiang Province, PR China. Strain CWB-1T grew at 4-40 °C (optimum, 30-35 °C), pH 6.5-9.0 (optimum, pH 6.5-7.0) and with 0.5-5.5 % (w/v) NaCl (optimum, 2.5-3.0 %). Phylogenetic analyses based on the 16S rRNA gene sequence and the whole genome sequence both revealed that strain CWB-1T belonged to the family Flavobacteriaceae. The strain had the highest similarity of the 16S rRNA gene sequence to Psychroserpens jangbogonensis PAMC 27130T (92.8 %). The genome of strain CWB-1T was 3 548 011 bp long with 36.3 % DNA G+C content. The predominant fatty acids (>10 %) in the CWB-1T cells were iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 1 (iso-C15 : 1 H/C13 : 0 3-OH). The major respiratory quinone was menaquinone-6 and the major polar lipids were phosphatidylethanolamine, an unidentified aminolipid and two unidentified lipids. Based on the phylogenetic analyses, as well as the phenotypic characteristics, a novel genus and species of the family Flavobacteriaceae, Paucihalobacter ruber gen. nov., sp. nov., is proposed. The type strain is CWB-1T (=KCTC 72450T=CGMCC 1.17149T).


Assuntos
Flavobacteriaceae/classificação , Sedimentos Geológicos/microbiologia , Lagos/microbiologia , Filogenia , Álcalis , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Concentração de Íons de Hidrogênio , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
Korean J Physiol Pharmacol ; 24(5): 423-431, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32830149

RESUMO

This study aimed to evaluate the effect of curcumin on brain hypoxicischemic (HI) damage in neonatal rats and whether the phosphoinositide 3-kinase (PI3K)/Akt/vascular endothelial growth factor (VEGF) signaling pathway is involved. Brain HI damage models were established in neonatal rats, which received the following treatments: curcumin by intraperitoneal injection before injury, insulin-like growth factor 1 (IGF-1) by subcutaneous injection after injury, and VEGF by intracerebroventricular injection after injury. This was followed by neurological evaluation, hemodynamic measurements, histopathological assessment, TUNEL assay, flow cytometry, and western blotting to assess the expression of p-PI3K, PI3K, p-Akt, Akt, and VEGF. Compared with rats that underwent sham operation, rats with brain HI damage showed remarkably increased neurological deficits, reduced right blood flow volume, elevated blood viscosity and haematocrit, and aggravated cell damage and apoptosis; these injuries were significantly improved by curcumin pretreatment. Meanwhile, brain HI damage induced the overexpression of p-PI3K, p-Akt, and VEGF, while curcumin pretreatment inhibited the expression of these proteins. In addition, IGF-1 treatment rescued the curcumin-induced down-regulated expression of p- PI3K, p-Akt, and VEGF, and VEGF overexpression counteracted the inhibitory effect of curcumin on brain HI damage. Overall, pretreatment with curcumin protected against brain HI damage by targeting VEGF via the PI3K/Akt signaling pathway in neonatal rats.

7.
BMC Pediatr ; 19(1): 495, 2019 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-31830932

RESUMO

BACKGROUND: This study aims to investigate the application value of three-dimensional arterial spin labeling (3DASL) in investigating cerebral blood flow dynamics in full-term neonates. METHODS: A total of 60 full-term neonates without known intracranial pathology were recruited for 3DASL examination. These neonates were divided into three groups: 1-3 day group, 4-7 day group, and 8-15 day group. On the cerebral blood flow (CBF) images, regions of interest (ROI) were selected from the frontal white matter, parietal white matter, basal ganglia, corona radiata, thalamus and brainstem, and the CBF values of each ROI were recorded. The CBF values of ROIs at bilaterally symmetric locations, the values of each ROI between males and females, and the values of each ROI among these three different age groups were compared. RESULTS: The difference in CBF values of the frontal white matter, parietal white matter, basal ganglia, corona radiata and thalamus at the bilateral symmetric positions were not statistically significant. There was no statistical difference in the CBF values of each brain region between the male and female groups. The CBF values at the basal ganglia region, corona radiata and parietal white matter were higher in the 8-15 day group, when compared to the 1-3 day and 4-7 day groups (P < 0.05). The CBF value at the basal ganglia region was higher in the 4-7 day group, when compared to the 1-3 day group (P < 0.05). The CBF value at the frontal white matter was lower in the 4-7 day group, when compared to the 1-3 day and 8-15 day group (P < 0.05). The CBF value at the brainstem was higher in the 4-7 day group, when compared to the 1-3 day and 8-15 day groups (P < 0.05). CONCLUSION: The 3DASL can quantitatively measure CBF, and be used to evaluate cerebral hemodynamics in neonates. The basal ganglia region and corona radiata CBF increases with the increase in neonatal diurnal age.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Imageamento Tridimensional , Imagem de Perfusão , Fluxo Sanguíneo Regional , Feminino , Humanos , Recém-Nascido , Masculino , Valores de Referência , Marcadores de Spin , Nascimento a Termo
8.
Stem Cell Res Ther ; 10(1): 294, 2019 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547879

RESUMO

INTRODUCTION: Accumulation of vascular smooth muscle cells (VSMCs) within the neointimal region is a hallmark of atherosclerosis and vessel injury. Evidence has shown that Sca-1-positive (Sca-1+) progenitor cells residing in the vascular adventitia play a crucial role in VSMC assemblages and intimal lesions. However, the underlying mechanisms, especially in the circumstances of vascular injury, remain unknown. METHODS AND RESULTS: The neointimal formation model in rats was established by carotid artery balloon injury using a 2F-Forgaty catheter. Most Sca-1+ cells first appeared at the adventitia of the vascular wall. S100B expressions were highest within the adventitia on the first day after vessel injury. Along with the sequentially increasing trend of S100B expression in the intima, media, and adventitia, respectively, the numbers of Sca-1+ cells were prominently increased at the media or neointima during the time course of neointimal formation. Furthermore, the Sca-1+ cells were markedly increased in the tunica media on the third day of vessel injury, SDF-1α expressions were obviously increased, and SDF-1α levels and Sca-1+ cells were almost synchronously increased within the neointima on the seventh day of vessel injury. These effects could effectually be reversed by knockdown of S100B by shRNA, RAGE inhibitor (SPF-ZM1), or CXCR4 blocker (AMD3100), indicating that migration of Sca-1+ cells from the adventitia into the neointima was associated with S100B/RAGE and SDF-1α/CXCR4. More importantly, the intermediate state of double-positive Sca-1+ and α-SMA cells was first found in the neointima of injured arteries, which could be substantially abrogated by using shRNA for S100B or blockade of CXCR4. S100B dose-dependently regulated SDF-1α expressions in VSMCs by activating PI3K/AKT and NF-κB, which were markedly abolished by PI3K/AKT inhibitor wortmannin and enhanced by p65 blocker PDTC. Furthermore, S100B was involved in human umbilical cord-derived Sca-1+ progenitor cells' differentiation into VSMCs, especially in maintaining the intermediate state of double-positive Sca-1+ and α-SMA. CONCLUSIONS: S100B triggered neointimal formation in rat injured arteries by maintaining the intermediate state of double-positive Sca-1+ progenitor and VSMCs, which were associated with direct activation of RAGE by S100B and indirect induction of SDF-1α by activating PI3K/AKT and NF-κB.


Assuntos
Ataxina-1/metabolismo , Lesões das Artérias Carótidas/metabolismo , Mioblastos/metabolismo , Miócitos de Músculo Liso/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Túnica Adventícia/citologia , Túnica Adventícia/fisiologia , Animais , Ataxina-1/genética , Lesões das Artérias Carótidas/patologia , Células Cultivadas , Humanos , Músculo Liso Vascular/citologia , Mioblastos/citologia , Miócitos de Músculo Liso/citologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Regeneração , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Túnica Íntima/citologia , Túnica Íntima/fisiologia
9.
J Cell Physiol ; 234(12): 22921-22934, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31148189

RESUMO

Bax triggers cell apoptosis by permeabilizing the outer mitochondrial membrane, leading to membrane potential loss and cytochrome c release. However, it is unclear if proteasomal degradation of Bax is involved in the apoptotic process, especially in heart ischemia-reperfusion (I/R)-induced injury. In the present study, KPC1 expression was heightened in left ventricular cardiomyocytes of patients with coronary heart disease (CHD), in I/R-myocardium in vivo and in hypoxia and reoxygenation (H/R)-induced cardiomyocytes in vitro. Overexpression of KPC1 reduced infarction size and cell apoptosis in I/R rat hearts. Similarly, the forced expression of KPC1 restored mitochondrial membrane potential (MMP) and cytochrome c release driven by H/R in H9c2 cells, whereas reducing cell apoptosis, and knockdown of KPC1 by short-hairpin RNA (shRNA) deteriorated cell apoptosis induced by H/R. Mechanistically, forced expression of KPC1 promoted Bax protein degradation, which was abolished by proteasome inhibitor MG132, suggesting that KPC1 promoted proteasomal degradation of Bax. Furthermore, KPC1 prevented basal and apoptotic stress-induced Bax translocation to mitochondria. Bax can be a novel target for the antiapoptotic effects of KPC1 on I/R-induced cardiomyocyte apoptosis and render mechanistic penetration into at least a subset of the mitochondrial effects of KPC1.


Assuntos
Doença das Coronárias/genética , Mitocôndrias/genética , Complexos Ubiquitina-Proteína Ligase/genética , Proteína X Associada a bcl-2/genética , Animais , Apoptose/genética , Hipóxia Celular/genética , Sobrevivência Celular/genética , Doença das Coronárias/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Humanos , Potencial da Membrana Mitocondrial/genética , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteólise , Ratos , Transdução de Sinais/genética
10.
Ying Yong Sheng Tai Xue Bao ; 30(1): 10-20, 2019 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-30907520

RESUMO

In China, fluoride pollution in soil is severe and poses a serious threat to human health and ecological security. However, how to control fluorine-contaminated soil has not received widespread attention. Here, we summarized fluorine speciation in soil and its main chemical reactions in water-soil system and reviewed the research progress on the remediation of fluorine-contaminated soils. Then, we proposed the focus of future research on fluorine-contaminated soil remediation. The aim of this review was providing the reference for the remediation of fluoride-contaminated soil. There are five forms of fluorine in soils, with the proportion of residual fluorine being over 90%. The reactions of fluorine in the soil solution mainly include precipitation-dissolution, complexation-dissociation, and adsorption-desorption. At present, the remediation technology of fluorine contaminated soil mainly focused on chemo-immobilization, chemical leaching, electrokinetic remediation, and phytoremediation. Clarifying the combined forms of fluorine in soil, screening functional microorga-nisms and plants, developing the combined remediation technology will be the focus of future research. Ultimately, on site fluorine-contaminated soil remediation could be implemented.


Assuntos
Recuperação e Remediação Ambiental , Flúor/análise , Poluentes do Solo/análise , Solo/química , Poluentes do Solo/química
11.
Stem Cell Res Ther ; 10(1): 70, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819239

RESUMO

AIM: The objective of this study is to determine if exuberant sympathetic nerve activity is involved in muscle satellite cell differentiation and myoblast fusion. METHODS AND RESULTS: By using immunoassaying and western blot analyses, we found that ß1 and ß2-adrenergic receptors (AdR) were expressed in C2C12 cells. The differentiated satellite cells exhibited an increased expression of ß2-AdR, as compared with the proliferating cells. Continuous exposure of isoprenaline (ISO), a ß-AdR agonist, delayed C2C12 cell differentiation, and myoblast fusion in time- and dose-dependent manner. ISO also increased short myotube numbers while decreasing long myotube numbers, consistent with the greater reduction in MyHC1, MyHC2a, and MyHC2x expression. Moreover, continuous exposure of ISO gradually decreased the ratio of PKA RI/RII, and PKA RI activator efficiently reversed the ISO effect on C2C12 cell differentiation and myoblast fusion while PKA inhibitor H-89 deteriorated the effects. Continuous single-dose ISO increased ß1-AdR expression in C2C12 cells. More importantly, the cells showed enhanced phospho-ERK1/2 levels, resulting in increasing phospho-ß2-AdR levels while decreasing ß2-AdR levels, and the specific effects could be abolished by ERK1/2 inhibitor. Furthermore, continuous exposure of ISO induced FOXO1 nuclear translocation and increased the levels of FOXO1 in nuclear extracts while reducing pAKT, p-p38MAPK, and pFOXO1 levels. Conversely, blockade of ERK1/2 signaling partially abrogated ISO effects on AKT, p38MAPK, and FOXO1signaling, which partially restored C2C12 cell differentiation and myoblast fusion, leading to an increase in the numbers of medium myotube along with the increased expression of MyHC1 and MyHC2a. CONCLUSION: Continuous exposure of ISO impedes satellite cell differentiation and myoblast fusion, at least in part, through PKA-ERK1/2-FOXO1 signaling pathways, which were associated with the reduced ß2-AdR and increased ß1-AdR levels.


Assuntos
Agonistas de Receptores Adrenérgicos beta 1/farmacologia , Diferenciação Celular/efeitos dos fármacos , Isoproterenol/farmacologia , Mioblastos/efeitos dos fármacos , Animais , Fusão Celular , Proliferação de Células/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Desenvolvimento Muscular/efeitos dos fármacos , Mioblastos/metabolismo , Cadeias Pesadas de Miosina/genética , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética
12.
Zhen Ci Yan Jiu ; 43(10): 632-9, 2018 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-30365258

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the rhythm of running-wheel activity of hepatocellular carcinoma (HCC) mice and the expression of Per 1 and Per 2 (circadian rhythm genes) in the hypothalamic suprachiasmatic nucleus (SCN), so as to investigate its mechanism underlying regulating circadian rhythm. METHODS: A total of 108 male C 57 BL / 6 J mice were randomly divided into control, HCC model and EA groups which were further assigned to six zeitbeger (environmental light-dark cycle) time (ZT) point (ZT 0, ZT 4, ZT 8, ZT 12, ZT 16 and ZT 20) subgroups. The HCC model was established by injection of H 22 cancer cell (abdominal 3rd generation, 10 µL) suspension into the larger live lobe. Mice of the control group received saline injection of the liver lobe. EA (2 Hz/15 Hz, 0.2 mA) was applied to bilateral "Ganshu" (BL 18) and "Zhiyang" (GV 9) for 15 min, once daily for 10 days. Mice of the control and model groups received the same binding-fixing to those of the EA group. Circadian running-wheel activity of 12 h∶12 h light darkness (LD) cycle (activity onset and acrophase of actogram, amplitude or peak of periodogram) was recorded by using ClockLab (ACT-500) software and analyzed by MATLAB (R 2007 b) before and after EA treatment. The pathological changes of liver cells were observed under light microscope after sectioning and H.E. staining. The expression levels of Per 1 mRNA and Per 2 mRNA in the liver tissues were determined by fluorogenic quantitative real time-PCR. RESULTS: (1) Following modeling, the amplitude of periodogram of running-wheel activity was significantly lowered at ZT 0, ZT 4, ZT 8, ZT 12, ZT 16, and ZT 20 relevant to the control group (P<0.05). After EA intervention, the amplitude of periodogram at ZT 8 (15:00) was considerably increased relevant to the model group (P<0.05), and the acrophase at ZT 8 was remarkably advanced (P<0.05). No significant changes were found in the onset time and periods of periodogram at the 6 time-points after modeling and EA intervention (P>0.05). (2) The expression levels of Per 1 mRNA and Per 2 mRNA in the SCN were significantly up-regulated at the 6 time-points in the model group relevant to the control group (P<0.05), and obviously down-regulated at ZT 8 after EA intervention relevant to the model group (P<0.05).. CONCLUSION: EA can benignly regulate the rhythm of running-wheel activity of HCC mice, which may be closely related to its effect in down-regulating the expression of circadian rhythm genes Per 1 and Per 2 in the SCN.


Assuntos
Carcinoma Hepatocelular , Eletroacupuntura , Neoplasias Hepáticas , Pontos de Acupuntura , Animais , Ritmo Circadiano , Masculino , Camundongos , Núcleo Supraquiasmático
13.
Environ Sci Pollut Res Int ; 25(26): 26351-26360, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29981021

RESUMO

A new strain SWH-15 was successfully isolated after initial electrokinetic remediation experiment using the same saline soil sampled from Shengli Oilfield, China. Four methods (morphological and biochemical characteristics, whole-cell fatty acid methyl esters (FAMEs) analysis, 16S rRNA sequence analysis and DNA G + C content and DNA-DNA hybridization analysis) were used to identify the taxonomic status of SWH-15 and confirmed that SWH-15 was a novel species of the Bacillus (B.) cereus group. Then, we assessed the degrading ability of the novel strain SWH-15 to crude oil through a microcosm experiment with four treatments, including control (CK), bioremediation using SWH-15 (Bio), electrokinetic remediation (EK), and combined bioremediation and electrokinetic remediation (Bio + EK). The results showed that the Bio + EK combined remediation treatment was more effective than the CK, Bio, and EK treatments in degrading crude oil contaminants. Bioaugmentation, by addition of the strain SWH-15 had synergistic effect with EK in Bio + EK treatment. Bacterial community analysis showed that electrokinetic remediation alone significantly altered the bacterial community of the saline soil. The addition of the strain SWH-15 alone had a weak effect on the bacterial community. However, the strain SWH-15 boosted the growth of other bacterial species in the metabolic network and weakened the impact of electrical field on the whole bacterial community structure in the Bio + EK treatment.


Assuntos
Bacillus cereus/isolamento & purificação , Petróleo/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bacillus cereus/genética , Bacillus cereus/metabolismo , Biodegradação Ambiental , China , Eletricidade , Recuperação e Remediação Ambiental , Ácidos Graxos/metabolismo , Campos de Petróleo e Gás , Poluição por Petróleo , Fenótipo , RNA Ribossômico 16S/genética , Tolerância ao Sal
14.
Cell Physiol Biochem ; 48(2): 433-449, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30016789

RESUMO

BACKGROUND/AIMS: Vagus nerve stimulation (VNS) suppresses arrhythmic activity and minimizes cardiomyocyte injury. However, how VNS affects angiogenesis/arteriogenesis in infarcted hearts, is poorly understood. METHODS: Myocardial infarction (MI) was achieved by ligation of the left anterior descending coronary artery (LAD) in rats. 7 days after LAD, stainless-steel wires were looped around the left and right vagal nerve in the neck for vagus nerve stimulation (VNS). The vagal nerve was stimulated with regular pulses of 0.2ms duration at 20 Hz for 10 seconds every minute for 4 hours, and then ACh levels by ELISA in cardiac tissue and serum were evaluated for its release after VNS. Three and 14 days after VNS, Real-time PCR, immunostaining and western blot were respectively used to determine VEGF-A/B expressions and α-SMA- and CD31-postive vessels in VNS-hearts with pretreatment of α7-nAChR blocker mecamylamine (10 mg/kg, ip) or mACh-R blocker atropine (10 mg/kg, ip) for 1 hour. The coronary function and left ventricular performance were analyzed by Langendorff system and hemodynamic parameters in VNS-hearts with pretreatment of VEGF-A/B-knockdown or VEGFR blocker AMG706. Coronary arterial endothelial cells proliferation, migration and tube formation were evaluated for angiogenesis following the stimulation of VNS in coronary arterial smooth muscle cells (VSMCs). RESULTS: VNS has been shown to stimulate VEGF-A and VEGF-B expressions in coronary arterial smooth muscle cells (VSMCs) and endothelial cells (ECs) with an increase of α-SMA- and CD31-postive vessel number in infarcted hearts. The VNS-induced VEGF-A/B expressions and angiogenesis were abolished by m-AChR inhibitor atropine and α7-nAChR blocker mecamylamine in vivo. Interestingly, knockdown of VEGF-A by shRNA mainly reduced VNS-mediated formation of CD31+ microvessels. In contrast, knockdown of VEGF-B powerfully abrogated VNS-induced formation of α-SMA+ vessels. Consistently, VNS-induced VEGF-A showed a greater effect on EC tube formation as compared to VNS-induced VEGF-B. Moreover, VEGF-A promoted EC proliferation and VSMC migration while VEGF-B induced VSMC proliferation and EC migration in vitro. Mechanistically, vagal neurotransmitter acetylcholine stimulated VEGF-A/B expressions through m/nACh-R/PI3K/Akt/Sp1 pathway in EC. Functionally, VNS improved the coronary function and left ventricular performance. However, blockade of VEGF receptor by antagonist AMG706 or knockdown of VEGF-A or VEGF-B by shRNA significantly diminished the beneficial effects of VNS on ventricular performance. CONCLUSION: VNS promoted angiogenesis/arteriogenesis to repair the infracted heart through the synergistic effects of VEGF-A and VEGF-B.


Assuntos
Infarto do Miocárdio/terapia , Estimulação do Nervo Vago , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator B de Crescimento do Endotélio Vascular/metabolismo , Acetilcolina/análise , Acetilcolina/sangue , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Indóis/farmacologia , Masculino , Microvasos/citologia , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Niacinamida/administração & dosagem , Niacinamida/farmacologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Muscarínicos/química , Receptores Muscarínicos/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Fator B de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator B de Crescimento do Endotélio Vascular/genética , Receptor Nicotínico de Acetilcolina alfa7/antagonistas & inibidores , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
15.
Ecotoxicol Environ Saf ; 157: 276-284, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29627411

RESUMO

The Yellow River Delta (YRD) is a typical region where oil fields generally overlap cities and towns, leading to complex soil contamination from both the oil fields and human activities. To clarify the distribution, speciation, potential sources and health risk of polycyclic aromatic hydrocarbons (PAHs) in soils of border regions between oil fields and suburbs of the YRD, 138 soil samples (0-20 cm) were collected among 12 sampling sites located around oil wells with different extraction histories. The 16 priority control PAHs (16PAHs), as selected by the United States Environmental Protection Agency (USEPA), were extracted via an accelerated solvent extraction and detected by GC-MS. The results showed that soils of the study area were generally polluted by the 16PAHs. Among these pollutions, chrysene and phenanthrene were the dominant components, and 4-ring PAHs were the most abundant. A typical temporal distribution pattern of the 16PAHs was revealed in soils from different sampling sites around oil wells with different exploitation histories. The concentrations of total 16PAHs and high-ring PAHs (HPAHs) both increased with the extraction time of the nearby oil wells. Individual PAH ratios and PCA method revealed that the 16PAHs in soil with newly developed oil wells were mainly from petroleum pollutants, whereas PAHs in soils around oil wells with a long exploitation history were probably from petroleum contamination; combustion of petroleum, fuel, and biomass; and degradation and migration of PAHs from petroleum. Monte Carlo simulation was used to evaluate the health risks of the 7 carcinogenic PAHs and 9 non-carcinogenic PAHs in the study area. The results indicated that ingestion and dermal contact were the predominant pathways of exposure to PAH residues in soils. Both the carcinogenic and non-carcinogenic burden of the 16PAHs in soils of the oil field increased significantly with exploitation time of nearby oil wells.


Assuntos
Monitoramento Ambiental/métodos , Campos de Petróleo e Gás , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solo/química , China , Cidades , Humanos , Medição de Risco
16.
Jpn J Radiol ; 36(5): 345-350, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29616398

RESUMO

PURPOSE: To investigate the effect of automatic spectral imaging protocol selection (ASIS) and adaptive statistical iterative reconstruction (ASIR) technology in reducing radiation and contrast dosage. METHODS: Sixty-four patients were randomly divided into two groups for abdominal computed tomography (CT): the experiment group with ASIS plus 50% ASIR and the control with 120 kVp voltage. RESULTS: The CT dose-index volume decreased by 23.68 and 23.57% and the dose-length product dropped by 25.59 and 18.45% in the arterial and portal venous phases, respectively, in the experiment than control group. The contrast dose was reduced by 16.86% in the experiment group. In the 55 keV + 50% ASIR group, the arterial contrast-to-noise ratio and scores were significantly (P < 0.05) higher than in the control group in the arterial phase while the portal contrast-to-noise ratio and scores were not significantly different between the two groups (P > 0.05). CONCLUSION: The ASIS technique plus 50% ASIR can enhance image quality of the abdominal structures while decreasing the radiation and contrast dosage compared with the conventional scan mode.


Assuntos
Abdome/irrigação sanguínea , Abdome/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste/administração & dosagem , Processamento de Imagem Assistida por Computador/métodos , Doses de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
17.
Data Brief ; 16: 266-270, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29204471

RESUMO

In the previous report, Meox1 was found to promote SMCs phenotypic modulation and injury-induced vascular remodeling by regulating the FAK-ERK1/2-autophagy signaling cascade (Wu et al., 2017) [1]. Here, we presented new original data on the involvement of Mesoderm/mesenchyme homeobox gene l (Meox1) in balloon-injury-induced neointima formation of rat. In rat carotid artery balloon injury model to induce vascular remodeling, Meox1 was induced in vascular smooth muscle cell (SMCs) of rat carotid arteries. Most proliferating cell nuclear antigen (PCNA)-positive cells also expressed Meox1. These data suggested that Meox1 may be involved in SMCs proliferation during injury-induced neointima formation. Furthermore, knocked down its expression in injured arteries by adenoviral delivery of Meox1 short hairpin RNA (shRNA) (shMeox1), neointima formation was significantly inhibited. Elastin staining also confirmed the reduction of neointima in Meox1 shRNA-transduced arteries. Moreover, knockdown of Meox1 decreased the collagen production/deposition that was significantly increased in neointima induced by balloon injury.

18.
Int J Cardiol ; 251: 82-89, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29113690

RESUMO

AIMS: To investigate the role of mesoderm/mesenchyme homeobox gene l (Meox1) in vascular smooth muscle cells (SMCs) phenotypic modulation during vascular remodeling. METHODS AND RESULTS: By using immunostaining, Western blot, and histological analyses, we found that Meox1 was up-regulated in PDGF-BB-treated SMCs in vitro and balloon injury-induced arterial SMCs in vivo. Meox1 knockdown by shRNA restored the expression of contractile SMCs phenotype markers including smooth muscle α-actin (α-SMA) and calponin. In contrast, overexpression of Moex1 inhibited α-SMA and calponin expressions while inducing the expressions of synthetic SMCs phenotype markers such as matrix gla protein, osteopontin, and proliferating cell nuclear antigen. Mechanistically, Meox1 mediated the SMCs phenotypic modulation through FAK-ERK1/2 signaling, which appears to induce autophagy in SMCs. In vivo, knockdown of Meox1 attenuated injury-induced neointima formation and promoted SMCs contractile proteins expressions. Meox1 knockdown also reduced the number of proliferating SMCs, suggesting that Meox1 was important for SMCs proliferation in vivo. Moreover, knockdown of Meox1 attenuated ERK1/2 signaling and autophagy markers expressions, suggesting that Meox1 may promote SMCs phenotypic modulation via ERK1/2 signaling-autophagy in vivo. CONCLUSION: Our data indicated that Meox1 promotes SMCs phenotypic modulation and injury-induced vascular remodeling by regulating the FAK-ERK1/2-autophagy signaling cascade. Thus, targeting Meox1 may be an attractive approach for treating proliferating vascular diseases.


Assuntos
Músculo Liso Vascular/citologia , Músculo Liso Vascular/fisiologia , Fenótipo , Fatores de Transcrição/deficiência , Remodelação Vascular/fisiologia , Animais , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Técnicas de Silenciamento de Genes/métodos , Proteínas de Homeodomínio , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição/biossíntese , Fatores de Transcrição/farmacologia , Remodelação Vascular/efeitos dos fármacos
19.
Biochim Biophys Acta Mol Basis Dis ; 1863(11): 2772-2782, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28693920

RESUMO

S100B is a biomarker of nervous system injury, but it is unknown if it is also involved in vascular injury. In the present study, we investigated S100B function in vascular remodeling following injury. Balloon injury in rat carotid artery progressively induced neointima formation while increasing S100B expression in both neointimal vascular smooth muscle (VSMC) and serum along with an induction of proliferating cell nuclear antigen (PCNA). Knockdown of S100B by its shRNA delivered by adenoviral transduction attenuated the PCNA expression and neointimal hyperplasia in vivo and suppressed PDGF-BB-induced VSMC proliferation and migration in vitro. Conversely, overexpression of S100B promoted VSMC proliferation and migration. Mechanistically, S100B altered VSMC phenotype by decreasing the contractile protein expression, which appeared to be mediated by NF-κB activity. S100B induced NF-κB-p65 gene transcription, protein expression and nuclear translocation. Blockade of NF-κB activity by its inhibitor reversed S100B-mediated downregulation of VSMC contractile protein and increase in VSMC proliferation and migration. It appeared that S100B regulated NF-κB expression through, at least partially, the Receptor for Advanced Glycation End products (RAGE) because RAGE inhibitor attenuated S100B-mediated NF-κB promoter activity as well as VSMC proliferation. Most importantly, S100B secreted from VSMC impaired endothelial tube formation in vitro, and knockdown of S100B promoted re-endothelialization of injury-denuded arteries in vivo. These data indicated that S100B is a novel regulator for vascular remodeling following injury and may serve as a potential biomarker for vascular damage or drug target for treating proliferative vascular diseases.


Assuntos
Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Neointima/metabolismo , Subunidade beta da Proteína Ligante de Cálcio S100/biossíntese , Remodelação Vascular , Animais , Regulação da Expressão Gênica , Músculo Liso Vascular/lesões , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Neointima/patologia , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Fator de Transcrição RelA/metabolismo
20.
Oncol Rep ; 38(2): 1075-1082, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28677798

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of malignant pancreatic tumor. MicroRNAs (miRNAs) are a group of small, non-protein coding, endogenous RNAs that play critical roles in tumorigenesis and progression of PDAC. In the present study, we demonstrated that miR-448 expression was downregulated in PDAC tissues and cell lines. Clinical association analysis indicated that low expression of miR-448 was associated with poor prognostic features and conferred a significant reduced survival of PDAC patients. Overexpression of miR-448 suppressed PDAC cell migration and invasion, while its loss showed the opposite effects on these cellular processes. In vivo experiments revealed that miR-488 restoration prohibited liver metastasis of PDAC in nude mice. Moreover, we found that Janus kinase 1 (JAK1) was a direct target gene of miR-448 in PDAC cells. We further demonstrated that the expression of JAK1 mRNA was upregulated in PDAC tissues. Notably, the expression of JAK1 mRNA was inversely correlated with the level of miR-448 in PDAC tissues. In addition, JAK1 knockdown showed similar effects of miR-448 on the metastasis of PDAC cells. JAK1/STAT3 pathway may be involved in the function of miR-448 in PDAC cells. Taken together, these findings suggest that miR-448 functions as a tumor suppressor in the development of PDAC through targeting the JAK1/STAT3 pathway.


Assuntos
Adenocarcinoma/prevenção & controle , Carcinoma Ductal Pancreático/prevenção & controle , Janus Quinase 1/antagonistas & inibidores , Neoplasias Hepáticas/prevenção & controle , MicroRNAs/genética , Neoplasias Pancreáticas/prevenção & controle , Fator de Transcrição STAT3/antagonistas & inibidores , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundário , Animais , Apoptose , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundário , Estudos de Casos e Controles , Movimento Celular , Proliferação de Células , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 1/genética , Janus Quinase 1/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Prognóstico , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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