Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 161
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Biomater Sci ; 7(10): 4060-4074, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31475710

RESUMO

Combined photothermal-chemotherapy guided by multimodal imaging is a promising strategy for cancer diagnosis and treatment. Multifunctional nanoparticles, such as those comprising organic and inorganic compounds, have been extensively investigated for combined photothermal-chemotherapy; however, their application is still limited by their potential long-term toxicity and lack of contrast properties. To solve these problems, in this study, a new type of multifunctional nanoparticle for combined photothermal-chemotherapy guided by dual-modality imaging was prepared with endogenous melanin by multistep emulsification to enhance tumor ablation. The nanoparticles were coated with poly(lactide-co-glycolic acid) (PLGA) and loaded with paclitaxel (PTX), encapsulated melanin and perfluoropentane (PFP). The materials in the nanoparticles were endogenous, ensuring high stability, biocompatibility, and biosafety. Nanoparticles irradiated with a laser, which induced their phase transformation into microbubbles, exhibited high photothermal conversion efficiency, thereby achieving photoacoustic (PA)/ultrasound (US) dual-modality imaging to determine tumor location, boundary, and size and to monitor drug distribution. Furthermore, optical droplet vaporization (ODV) of the nanoparticles could trigger the release of PTX; thus, these nanoparticles are a useful drug carrier. In vivo and in vitro experiments revealed that a strong synergistic antitumor effect was achieved by combining the photothermal properties of the nanoparticles with a chemotherapy drug. Importantly, the cavitation, thermoelastic expansion, and sonoporation caused by the phase transformation of the nanoparticles could directly damage the tumors. These processes also promoted the release, penetration and absorption of the drug, further enhancing the effect of combined photothermal-chemotherapy on tumor suppression. Therefore, the multifunctional nanoparticles prepared in this study provide a new strategy of using endogenous materials for controlled near-infrared (NIR)-responsive drug release and combined photothermal-chemotherapy guided by multimodal imaging.

2.
Rev Sci Instrum ; 90(7): 075101, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31370475

RESUMO

The magnetic flux leakage (MFL) evaluation is often used for the overhauling of oil extracting operation in the oil field to realize the real-time damage assessment of the pipeline. Since the MFL signal is affected by various noise sources in the field, this paper introduces the complementary ensemble empirical mode decomposition with adaptive noise (CEEMDAN). On the basis of this, a particle swarm optimization wavelet threshold (PSO-WT) method is proposed, and the signal reconstruction option is improved to extract the leakage magnetic flux signal of tubing defects. First, CEEMDAN is used to add pairs of positive and negative white noise to the MFL signal, and then the signal is decomposed into several intrinsic mode functions (IMFs). Second, the correlation coefficient selection limit is defined. Taking into account the characteristics of the decomposed signal, the useless IMFs and useful IMFs are selected from the IMF components, where some of the useful IMF components contain less noise. Third, the PSO-WT algorithm is combined to further filter the noisy and useful IMF components. Finally, the filtered IMF components and the pure useful IMF components are selected to reconstruct the signal. In the experiment, the ensemble empirical mode decomposition (EEMD) method and CEEMDAN are used to decompose the noisy MFL signals ensemble in the field. The MFL signal is reconstructed under the correlation coefficient selection. It can be seen from the comparison of EEMD that the MFL signal is reconstructed under the same conditions after CEEMDAN decomposition, and its signal-to-noise ratio is increased by 8%. At the same time, after CEEMDAN decomposition, the selected noisy useful IMFs are further filtered by the wavelet threshold (WT) method and the PSO-WT method. Also, it indicates that the reconstructed signal processed by PSO-WT is 17% higher than the reconstructed signal after WT processing.

3.
J Am Soc Nephrol ; 30(10): 2017-2026, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31444275

RESUMO

BACKGROUND: IgA nephropathy (IgAN) is the leading primary GN worldwide. The disease is thought to result from glomerular deposition of circulating immune complexes of IgG bound to galactose-deficient IgA1 (Gd-IgA1). However, routine immunofluorescence microscopy fails to detect IgG in many kidney biopsies from patients with IgAN and the specificity of IgG in immunodeposits has not been tested. METHODS: We used remnant frozen kidney-biopsy specimens from 34 patients with IgAN; 14 were IgG-positive and 20 were IgG-negative by routine immunofluorescence microscopy. Six patients with primary membranous nephropathy (MN) and eight with lupus nephritis (LN) served as controls. IgG in the kidney tissue was extracted and its amount determined by ELISA. IgG molecular integrity was assessed by SDS-PAGE immunoblotting. Antigenic specificity of extracted IgG was determined by ELISA using phospholipase A2 receptor (PLA2R) or Gd-IgA1 as antigen. In addition, ten other IgAN cases, six IgG-positive and four IgG-negative by routine immunofluorescence, were used for colocalization studies by confocal microscopy. RESULTS: IgG extracted from MN but not IgAN immunodeposits reacted with PLA2R. Conversely, IgG extracted from IgAN but not MN or LN immunodeposits reacted with Gd-IgA1. Even IgAN kidney-biopsy specimens without IgG by routine immunofluorescence microscopy had IgG specific for Gd-IgA1. Confocal microscopy confirmed the presence of IgG in the IgAN biopsies with colocalization of glomerular IgA and IgG. CONCLUSIONS: These results reveal for the first time that IgAN kidney biopsies, with or without IgG by routine immunofluorescence, contain Gd-IgA1-specific IgG autoantibodies. These findings support the importance of these autoantibodies in the pathogenesis of IgAN.

4.
J Biomed Mater Res A ; 107(10): 2272-2281, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31148352

RESUMO

Bioadaptive nanostructure coatings of hydroxyapatite (HAP) and TiO2 on titanium (Ti) implants are essential for biomaterial-tissue osteointegration. However, there is no specific report, so far, that focuses on the different influences of the two bioadaptive coatings on preosteoblast behaviors. Herein, adhesion, proliferation, and osteogenic potential of preosteoblast on HAP and TiO2 coatings with nanorod array topography were studied. XRD, TEM, and SAED analysis indicated that rod-like HAP nanoarray and anatase TiO2 nanoarray coatings were fabricated successfully, and there was insignificant difference in roughness and fibronectin adsorption of the two coatings. Adhesion and proliferation of MC3T3-E1 cells on the two coatings were of no significant difference, besides a larger projected area of the cells on HAP coating. MC3T3-E1 cells cultured on the HAP coating displayed significantly higher expression of runt-related transcription factor-2 (Runx2), osteocalcin (OCN) and collagen type-1 (Col I) after culture for 21 days compared with those on TiO2 coating, except alkaline phosphatase (ALP). This study provides beneficial suggestion for intelligent selection of biocoatings.

5.
Chemosphere ; 232: 9-17, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31152908

RESUMO

Amorphous molybdenum sulphide materials are attracting more attention in heterogeneous catalysis, gas adsorption and water remediation fields. Herein, a new type of amorphous molybdenum sulphide composite (poly(diallyldimethylammonium-MoS4), shorten as PDADMA-MoS4) was synthesized via a facile precipitation reaction. Metal adsorption tests of prepared PDADMA-MoS4 composite shows that Hg2+ and Pb2+ concentrations in solution can decrease from 10 ppm to <0.5 ppb level much lower than the drinking water requirement (<2 ppb) in 10 min. The metal adsorption isotherms suggest that maximum metal-uptake capacities are 1460.0 mg/g for Hg (pH = 5) and 433.7 mg/g for Hg (pH = 1), indicating that this sorbent works over a wide pH range (1.0-7.0) to effectively remove Hg from aqueous solution. More importantly, at very low pH = 1, this sorbent material exhibits extraordinarily high selectivity of Hg over Pb and Cu (separation factors ßHg/Cu=4.5×104 and ßHg/Pb=3.6×104). The excellent Hg capacity and selectivity at low pH region (pH < 2) has shed light on the new generation of adsorbent materials for acidic wastewater treatment.


Assuntos
Dissulfetos/química , Mercúrio/análise , Molibdênio/química , Eliminação de Resíduos Líquidos , Águas Residuárias/química , Adsorção , Concentração de Íons de Hidrogênio , Metais
6.
Sci Total Environ ; 659: 895-904, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096419

RESUMO

Magnetic Fe3O4-encapsulated C3N3S3 polymer/reduced graphene oxide composite (rGO-poly(C3N3S3)/Fe3O4) was synthesized to remove Pb(II) and Hg(II) from aqueous solutions. This material was characterized by X-ray Photoelectron Spectroscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, X-ray powder diffraction, N2 adsorption, etc. The results suggest that final composite exhibits two-dimensional (2D) nanosheet structure, in which Fe3O4 nanoparticles or clusters are encapsulated between the layers of rGO-poly(C3N3S3) matrix, preventing composite aggregation and nanoparticle detachment. The results of adsorption tests suggested high metal removal and short residence time to reach equilibrium. The adsorption kinetics data were well fitted by pseudo-second-order equation. The effect of metal concentration on adsorption was illustrated by Langmuir isotherm equation. Maximum metal-uptake capacities for Pb(II) and Hg(II) ions were 270.3 and 400.0 mg/g, respectively. High-resolution XPS spectra clearly illustrate the adsorption mechanism, in that Hg(II) preferentially binds to sulphur functional groups and Pb(II) tends to be adsorbed by nitrogen groups in poly(C3N3S3) matrix. Recycling performance of this composite was investigated in 15 consecutive adsorption-desorption cycles, after which the adsorption capacities for Pb(II), and Hg(II) ions remain stable thanks to Fe3O4 encapsulation into the rGO-poly(C3N3S3) matrix.

7.
Mol Plant Pathol ; 20(7): 895-906, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31074170

RESUMO

Sclerotinia sclerotiorum is a devastating necrotrophic fungal pathogen that infects over 400 species of plants worldwide. Reactive oxygen species (ROS) modulations are critical for the pathogenic development of S. sclerotiorum. The fungus applies enzymatic and non-enzymatic antioxidants to cope with the oxidative stress during the infection processes. Survival factor 1 was identified and characterized to promote survival under conditions of oxidative stress in Saccharomyes cerevisiae. In this research, a gene named SsSvf1 was predicted to encode a survival factor 1 homologue in S. sclerotiorum. SsSvf1 transcripts showed high expression levels in hyphae under oxidative stress. Silencing of SsSvf1 resulted in increased sensitivity to oxidative stress in culture and increased levels of intracellular ROS. Transcripts of SsSvf1 showed a dramatic increase during the initial stage of infection and the gene-silenced strains displayed reduced virulence on oilseed rape and Arabidopsis thaliana. Inhibition of plant ROS production partially restores virulence of SsSvf1 gene-silenced strains. SsSvf1 gene-silenced strains exhibited normal oxalate production, but were impaired in compound appressorium formation and cell wall integrity. The results suggest that SsSvf1 is involved in coping with ROS during fungal-host interactions and plays a crucial role in the pathogenicity of S. sclerotiorum.

8.
Nat Commun ; 10(1): 1684, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975991

RESUMO

Obesity triggers the development of non-alcoholic fatty liver disease (NAFLD), which involves alterations of regulatory transcription networks and epigenomes in hepatocytes. Here we demonstrate that G protein pathway suppressor 2 (GPS2), a subunit of the nuclear receptor corepressor (NCOR) and histone deacetylase 3 (HDAC3) complex, has a central role in these alterations and accelerates the progression of NAFLD towards non-alcoholic steatohepatitis (NASH). Hepatocyte-specific Gps2 knockout in mice alleviates the development of diet-induced steatosis and fibrosis and causes activation of lipid catabolic genes. Integrative cistrome, epigenome and transcriptome analysis identifies the lipid-sensing peroxisome proliferator-activated receptor α (PPARα, NR1C1) as a direct GPS2 target. Liver gene expression data from human patients reveal that Gps2 expression positively correlates with a NASH/fibrosis gene signature. Collectively, our data suggest that the GPS2-PPARα partnership in hepatocytes coordinates the progression of NAFLD in mice and in humans and thus might be of therapeutic interest.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR alfa/metabolismo , Animais , Biópsia , Conjuntos de Dados como Assunto , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Epigênese Genética , Fibrose , Células HEK293 , Hepatócitos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/genética
10.
Bioresour Technol ; 275: 421-424, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30611623

RESUMO

Froth flotation has been proved to be a promising approach for commercial scale harvesting of microalgae. However, all the surfactants used in the microalgae flotation harvesting process are conventional monomeric surfactants contain a single similar hydrophobic group in the molecule, which results in a low harvesting efficiency. In this work, a novel Gemini surfactant, N,N'-bis(cetyldimethyl)-1,4-butane diammonium dibromide (BCBD) was prepared, and originally recommended as a collector for froth flotation harvesting of Chlorella vulgaris from culture medium. The performance of BCBD was compared with the results acquired using its conventional monomeric surfactant cetyl trimethyl ammonium bromide (CTAB). The bench-scale flotation results showed that BCBD had excellent collecting power for Chlorella vulgaris. Achieving the obviously superior flotation harvesting performance (flotation recovery increased by 21.4% and enrichment ratio increased by 22.9), the dosage of Gemini type BCBD collector is five times less than that of monomeric CTAB collector.


Assuntos
Brometos/isolamento & purificação , Chlorella vulgaris/química , Microalgas/química , Tensoativos/isolamento & purificação
11.
Sci Total Environ ; 655: 1104-1112, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30577104

RESUMO

Butane-1,4-bis(dodecyl dimethyl ammonium bromide) (gBDDA) and dodecyl trimethyl ammonium bromide (DTMA) in same stoichiometric amounts were applied to modify montmorillonite (Mt) under microwave and ultrasound conditions. The composition and structure of products were obtained through multiple characterizations including XRD, FTIR, TG/DTG, SEM, TEM, and N2 adsorption/desorption measurements, and the adsorption performance of chromate and phenol on these products were also investigated. Intercalations of gBDDA and DTMA into interlayer space of Mt were observed, but the amount of anchored modifier on the external surface was larger for gBDDA compared with DTMA when the stoichiometric amount of modifier larger than 1.0 times cation exchange capacity of Mt was added. Although there was no significant difference in morphology among products, the interlayer space distance, specific surface area, and pore size distribution were closely associated with the species and amount of applied modifier. Adsorption of phenol on products through partition mechanism relied on not only organic content, but also the configuration of modifier. Meanwhile, adsorption of chromate mainly depended on the presence of counter ion (bromide), which accounted for the high adsorption capacity and initial adsorption rate on gOMt-0.75. The fitting parameters of adsorption results using pseudo-second order model and Freundlich model suggested that gBDDA-modified Mt could sequester phenol or chromate in the faster manner with higher affinity. Compared with the conventional surfactant such as DTMA, the study revealed that, using gemini surfactant such as gBDDA to modify Mt would significantly reduce or even has the potential to eradicate the secondary pollution by modifier release during adsorption process. This study provides a new direction for Mt modification intended to be used as adsorbents to treat polluted water with high standards such as drinking water.

12.
Mol Med Rep ; 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30431132

RESUMO

The present study aimed to develop novel diagnostic methods for polycystic ovarian syndrome (PCOS) by screening and identifying specific PCOS­associated metabolic markers using plasma metabolomics. Ultra­performance liquid chromatography/quadrapole­time of flight­mass spectrometry was adopted to establish the plasma metabolic fingerprint of 49 patients and 50 normal controls, in order to screen the potential metabolic markers. In addition, these markers were integrated with the clinical indexes, followed by focused analysis to obtain diagnostic markers. The present results demonstrated that not only was the concentration of palmitoyl sphingomyelin in plasma of patients with PCOS significantly increased; however, a statistically significant difference between the two PCOS subgroups was additionally demonstrated. At the same time, the concentrations of cyclic guanosine monophosphate (cGMP) and dehydroepiandrosterone sulphate in the plasma of patients of the subgroup 1 were significantly elevated. These markers were additionally integrated with the clinical index number of follicles in the left ovary and high­density lipoprotein (HDL­C), followed by receiver operating characteristic curve analysis, which demonstrated a diagnostic accuracy of ~90% in the control and the two subgroups. The integrated marker system consisting of palmitoyl sphingomyelin, cGMP and androsterone sulfate, as well as the number of left follicles and HDL­C may be used for the accurate diagnosis and classification of PCOS. These results confirmed that the abnormalities in hormone metabolism and lipid metabolism disorder were primarily involved in the onset of PCOS.

13.
Artigo em Inglês | MEDLINE | ID: mdl-30398062

RESUMO

Deep partial thickness burn wounds present big challenges due to the long healing time, large size and irregular shape, pain and reinjury at wound dressing changes, as well as scarring. The clinically effective therapy to alleviate pain at wound dressing changes, and the scar left on the skin after the healing of wound is still unavailable. To combat this, we develop a nanocomposite self-healing hydrogel that can be injected into irregular and deep burn wound beds and subsequently rapidly self-heal to reform into an integrated piece of hydrogel that thoroughly fills the wound area and protects the wound site from external environment, finally being painlessly removed by on-demand dissolving using amino acid solution at wound dressing changes, which accelerates deep partial thickness burn wound healing and prevents scarring. The hydrogel is made out of naturally occurring polymers, namely, water-soluble carboxymethyl chitosan (CMC) and rigid rod-like dialdehyde-modified cellulose nanocrystal (DACNC). They are cross-linked by dynamic Schiff-base linkages between amines from CMC and aldehydes from DACNC. The large aspect ratio and specific surface area of DACNC raise massive active junctions within the hydrogel, which can be readily broken and reformed, allowing hydrogel to rapidly self-heal. Moreover, DACNC serves as nanoreinforcing fillers to improve the hydrogel strength, which also restricts the "soft" CMC chains' motion when soaked in aqueous system, endowing high fluid uptake capacity (350%) to hydrogel while maintaining integrity. Cytotoxicity assay and three-dimensional cell culture demonstrate excellent biocompatibility of the hydrogel and capacity as extracellular matrix to support cell growth. This work opens a novel pathway to fabricate on-demand dissolvable self-healing hydrogels to speed deep partial thickness burn wound healing and eliminate pain at wound dressing changes and prevent scar formation.

14.
J Agric Food Chem ; 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30485094

RESUMO

Potassium fertilizer plays a critical role in increasing the food production. Carnallite is concentrated by reverse froth flotation and used as a raw material to produce potassium fertilizer (KCl) in agriculture. However, all the surfactants used in the carnallite reverse flotation process are conventional monomeric surfactants contain a single similar hydrophobic group in the molecule, which results in a low production efficiency. In this work, a new morpholine-based Gemini surfactant, 1,4-bis (morpholinododecylammonio) butane dibromide (BMBD) was prepared, and originally recommended as a collector for reverse froth flotation separation of halite (NaCl) from carnallite ore. The flotation results indicated BMBD had higher flotation recovery and stronger affinity of halite against carnallite, compared with conventional monomeric surfactant N-(n-Dodecyl) morpholine (DDM). FTIR spectra suggested that BMBD molecules were adsorbed on halite surface rather than the carnallite surface. Additionally, BMBD molecules can strongly reduce the surface tension of NaCl saturated solution. Considering the BMBD's unique properties, such as double reactive centers to mineral surfaces, double hydrophobic groups, and stronger surface tension reducing ability, made it be a superior collector for reverse flotation desalination from carnallite ores than DDM.

15.
J Virol ; 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30305355

RESUMO

The HIV-1 envelope (Env) glycans shield the surface of Env from the immune system and form integral interactions important for a functional Env. To understand how individual N-glycosylation sites (NGS) coordinate to form a dynamic shield and evade the immune system through mutations, we tracked 20 NGS in Env from HIV transmitted/founder (T/F) and immune-escape variants and their mutants involving the N262 glycan. NGS were profiled in a site-specific manner using a high-resolution mass spectrometry (MS)-based workflow. Using this site-specific quantitative heterogeneity profiling, we empirically characterized the interdependent NGS of a microdomain in the high-mannose patch (HMP). The changes (shifts) in NGS heterogeneity between the T/F and immune-escape variants defined a range of NGS that we further probed for exclusive combinations of sequons in the HMP microdomain using the Los Alamos HIV sequence database. The resultant sequon combinations, including the highly conserved NGS N262, N448, and N301, created an immune-escape map of the conserved and variable sequons in the HMP microdomain. This report provides details on how some clustered NGS form microdomains that can be identified and tracked across Env variants. These microdomains have a limited number of N-glycan-sequon combinations that may allow the anticipation of immune-escape variants.ImportanceThe Env of HIV is highly glycosylated and the sites of glycosylation can change as the virus mutates during immune evasion. Due to these changes, the glycan location and heterogeneity of surrounding N-glycosylation sites can be altered resulting in exposure of different glycan or proteoglycan surfaces while still producing a viable HIV variant. These changes present a need for vaccine developers to identify Env variants with epitopes most likely to induce durable protective responses. Here, we describe a means of anticipating HIV-1 immune evasion by dividing Env into N-glycan microdomains that have a limited number of N-glycan sequon combinations.

16.
Mol Genet Genomics ; 2018 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-30267144

RESUMO

The vasculature of higher plants is important with transport of both nutrient and information molecules. To understand the correspondence of this tissue in molecular responses under phosphate (Pi) deficiency, Plantago major, a model plant for vasculature biology study, was chosen in our analysis. After RNA-Seq and de novo transcriptome assembly of 24 libraries prepared from the vasculature of P. major, 37,309 unigenes with a mean length of 1571 base pairs were obtained. Upon 24 h of Pi deficiency, 237 genes were shown to be differentially expressed in the vasculature of P. major. Among these genes, only 27 have been previously identified to be specifically expressed in the vasculature tissues in other plant species. Temporal expression of several marker genes associated with Pi deficiency showed that the time period of first 24 h is at the beginning stage of more dynamic expression patterns. In this study, we found several physiological processes, e.g., "phosphate metabolism and remobilization", "sucrose metabolism, loading and synthesis", "plant hormone metabolism and signal transduction", "transcription factors", and "metabolism of other minerals", were mainly involved in early responses to Pi deficiency in the vasculature. A number of vasculature genes with promising roles in Pi deficiency adaptation have been identified and deserve further functional characterization. This study clearly demonstrated that plant vasculature is actively involved in Pi deficiency responses and understanding of this process may help to create plants proficient to offset Pi deficiency.

17.
Cell Rep ; 24(11): 2957-2971.e6, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30208320

RESUMO

Hypertrophic white adipose tissue (WAT) represents a maladaptive mechanism linked to the risk for developing type 2 diabetes in humans. However, the molecular events that predispose WAT to hypertrophy are poorly defined. Here, we demonstrate that adipocyte hypertrophy is triggered by loss of the corepressor GPS2 during obesity. Adipocyte-specific GPS2 deficiency in mice (GPS2 AKO) causes adipocyte hypertrophy, inflammation, and mitochondrial dysfunction during surplus energy. This phenotype is driven by HIF1A activation that orchestrates inadequate WAT remodeling and disrupts mitochondrial activity, which can be reversed by pharmacological or genetic HIF1A inhibition. Correlation analysis of gene expression in human adipose tissue reveals a negative relationship between GPS2 and HIF1A, adipocyte hypertrophy, and insulin resistance. We propose therefore that the obesity-associated loss of GPS2 in adipocytes predisposes for a maladaptive WAT expansion and a pro-diabetic status in mice and humans.

18.
Lasers Med Sci ; 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30069683

RESUMO

The success of endodontic treatment depends on the thorough removal of microorganisms from the root canal system. The search for new ways to eliminate the microorganisms is therefore justified. Nd:YAP is a laser that uses yttrium aluminum perovskite, doped with neodymium crystal, as active laser medium. We used the Nd:YAP laser in an in vitro experiment to evaluate the bactericidal effect of three parameters of Nd:YAP laser-activated irrigation on biofilms of Enterococcus faecalis in root canals. The canals of 45 extracted human single-root teeth were prepared on a #35 Mtwo instrument and contaminated with E. faecalis for 14 days. Forty infected single-root teeth were then randomly divided into four groups according to the irrigation agitation protocols as follows: 5.25% sodium hypochlorite (NaOCl), Nd:YAP laser (180 mJ) + NaOCl, Nd:YAP laser (280 mJ) + NaOCl, and Nd:YAP laser (360 mJ) + NaOCl. The remaining bacteria were counted immediately using the cell count method. Teeth were firstly spilt and one half examined by scanning electron microscopy (SEM). The other half involved examination of bacterial colonization in dentinal tubules using confocal laser scanning microscopy (CLSM). Nd:YAP laser (280 mJ) + NaOCl and Nd:YAP laser (360 mJ) + NaOCl completely removed the E. faecalis biofilms from the root canal walls and made it the cleanest among the treatment groups. Bacterial reductions in the treatment groups for dentinal tubules are presented in a descending order as follows: Nd:YAP laser (360 mJ) (53.7%), Nd:YAP laser (280 mJ) (51.5%) > Nd:YAP laser (180 mJ) (45.3%) > 5.25% NaOCl (31.9%) > control (19.3%) (p < 0.05). Nd:YAP laser of 280 mJ and 360 mJ showed effective bactericidal effect in removing E. faecalis biofilm from the root canal walls and dentinal tubules.

19.
Plant Cell Rep ; 37(12): 1611-1624, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30099610

RESUMO

KEY MESSAGE: The dynamic alterations of the physiological and molecular processes in reproductive stage soybean indicated the dramatic impact caused by drought. Drought is a major abiotic stress that limits soybean (Glycine max) production. Most prior studies were focused on either model species or crops that are at their vegetative stages. It is known that the reproductive stage of soybean is more susceptible to drought. Therefore, an understanding on the responsive mechanisms during this stage will not only be important for basic plant physiology, but the knowledge can also be used for crop improvement via either genetic engineering or molecular breeding. In this study, physiological measurements and RNA-Seq analysis were used to dissect the metabolic alterations and molecular responses in the leaves of soybean grown at drought condition. Photosynthesis rate, stomata conductance, transpiration, and water potential were reduced. The activities of SOD and CAT were increased, while the activity of POD stayed unchanged. A total of 2771 annotated genes with at least twofold changes were found to be differentially expressed in the drought-stressed plants in which 1798 genes were upregulated and 973 were downregulated. Via KEGG analysis, these genes were assigned to multiple molecular pathways, including ABA biogenesis, compatible compound accumulation, secondary metabolite synthesis, fatty acid desaturation, plant transcription factors, etc. The large number of differentially expressed genes and the diverse pathways indicated that soybean employs complicated mechanisms to cope with drought. Some of the identified genes and pathways can be used as targets for genetic engineering or molecular breeding to improve drought resistance in soybean.


Assuntos
Secas , Soja/genética , Soja/fisiologia , Estresse Fisiológico/genética , Transcriptoma/genética , Antioxidantes/metabolismo , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ontologia Genética , Temperatura Alta , Folhas de Planta/genética , Folhas de Planta/fisiologia , Reprodução/genética
20.
FASEB J ; : fj201801123R, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30153049

RESUMO

Macrophages play important roles in linking alterations of cholesterol metabolism and inflammation to the development of atherosclerosis. Previous studies have identified several positive and negative crosstalk mechanisms that connect cholesterol efflux and inflammation at the transcriptional level. Of particular relevance is that the expression of ATP-binding cassette transporter A1 ( Abca1), a main regulator of cholesterol efflux, can be induced by oxysterol receptor LXR agonists but also by bacterial endotoxins, such as LPS, that activate TLR4 signaling. However, the extent to which these pathways influence each other has remained incompletely understood. We investigated the possible role of the transcriptional coregulator G protein pathway suppressor 2 (GPS2) in LPS-induced Abca1 expression and cholesterol efflux in mouse and human macrophages. To activate Abca1, GPS2 cooperates with the LPS-inducible NF-κB subunit p65, but not with LXRs nor with corepressor complex subunits that otherwise cooperate with GPS2 to repress proinflammatory gene expression. Overall, our work identifies a regulatory chromatin component of crosstalk mechanisms between cholesterol efflux and inflammation that specifically affects ABCA1. Because GPS2 expression is down-regulated in some humans with obese and type 2 diabetes, the macrophage GPS-2/ABC-A1 pathway could be altered and contribute to atherogenesis.-Huang, Z., Liang, N., Damdimopoulos, A., Fan, R., Treuter, E. G protein pathway suppressor 2 (GPS2) links inflammation and cholesterol efflux by controlling lipopolysaccharide-induced ATP-binding cassette transporter A1 expression in macrophages.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA