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1.
Methods Mol Biol ; 2069: 197-228, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31523776

RESUMO

In vivo whole-animal optical (bioluminescence and fluorescence) imaging of Staphylococcus aureus infections has provided the opportunity to noninvasively and longitudinally monitor the dynamics of the bacterial burden and ensuing host immune responses in live anesthetized animals. Herein, we describe several different mouse models of S. aureus skin infection, skin inflammation, incisional/excisional wound infections, as well as mouse and rabbit models of orthopedic implant infection, which utilized this imaging technology. These animal models and imaging methodologies provide insights into the pathogenesis of these infections and innate and adaptive immune responses, as well as the preclinical evaluation of diagnostic and treatment modalities. Noninvasive approaches to investigate host-pathogen interactions are extremely important as virulent community-acquired methicillin-resistant S. aureus strains (CA-MRSA) are spreading through the normal human population, becoming more antibiotic resistant and creating a serious threat to public health.

2.
Nanoscale ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31681915

RESUMO

The intestinal epithelium is the main barrier for nanocarriers to orally deliver poorly water-soluble and absorbed agents. To further improve the transmembrane transport efficiency of polymeric micelles, intestinal oligopeptide transporter PepT1-targeted polymeric micelles were fabricated by Gly-Sar-conjugated poly(ethylene glycol)-poly(d,l-lactic acid). The functionalized polymeric micelles with about 40 nm diameter, uniform spherical morphology and favorable cytocompatibility with Caco-2 cells were demonstrated to distinctly enhance the cellular uptake and transmembrane transport of the loaded agents. The results of intestinal absorption strongly evidenced the higher accumulation of the micelles inside the epithelial cells, at the apical and basolateral sides of the epithelium within the villi in mice. Furthermore, the interaction of Gly-Sar decorated polymeric micelles with PepT1 was explored to promote the internalization of the micelles through fluorescence immunoassay, and the PepT1 level on the membrane of Caco-2 cells treated with the micelles appeared to change in a distinctly time-dependent manner. Both clathrin- and caveolae-mediated pathways were involved in the transcellular transport for undecorated polymeric micelles, while the transcellular transport pathway for Gly-Sar decorated ones was changed to be mainly mediated by clathrin and lipid rafts. The colocalization of Gly-Sar decorated micelles with the organelles observed by confocal laser scanning microscopy indicated that late endosomes, lysosomes, endoplasmic reticulum and Golgi apparatus appeared to participate in the intracellular trafficking progression of the micelles. These results suggested that PepT1-targeted polymeric micelles might have a strong potential to greatly promote the oral absorption of poorly water-soluble and absorbed agents.

3.
Br J Haematol ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31696939

RESUMO

Donor selection for older leukaemia patients undergoing haematopoietic cell transplant (HCT) is not well defined: outcomes might be improved with a younger offspring donor rather than an older human leukocyte antigen (HLA)-matched sibling donor (MSD). We extended our multicentre dataset. A total of 185 acute leukaemia patients (≥ 50 years) transplanted in first complete remission who received HCT from offspring (n = 62) or MSD (n = 123) were included. A 1:1 ratio matched-pair analysis was performed. We were able to match 54 offspring with 54 MSD patients. Outcomes were compared between the two matched-pair groups. The cumulative incidence of grade II/IV acute graft-versus-host disease (GVHD) (26% vs. 35%; P = 0·23) and chronic GVHD (37% vs. 24%; P = 0·19) was comparable between groups (MSD vs. offspring). The lower three-year transplant-related mortality (9% vs. 26%; P = 0·023) and relapse incidence (6% vs. 17%; P = 0·066) resulted in higher overall survival (85% vs. 58%; P = 0·003) and leukaemia-free survival (LFS) (85% vs. 56%; P = 0·001) in offspring HCT compared with that in MSD HCT. These data might favour a young offspring over an older MSD in patients >50 years. The current analyses confirm that non-HLA donor characteristics, such as kinship and donor age, rather than HLA disparity, predominantly influence survival in older acute leukaemia patients.

4.
Adv Healthc Mater ; : e1900823, 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31697456

RESUMO

Rapid and effective hemostatic materials have received wide attention not only in the battlefield but also in hospitals and clinics. Traditional hemostasis relies on materials with little designability which has many limitations. Nanohemostasis has been proposed since the use of peptides in hemostasis. Nanomaterials exhibit excellent adhesion, versatility, and designability compared to traditional materials, laying a good foundation for future hemostatic materials. This review first summarizes current hemostatic methods and materials, and then introduces several cutting-edge designs and applications of nanohemostatic materials such as polypeptide assembly, electrospinning of cyanoacrylate, and nanochitosan. Particularly, their advantages and working mechanisms are introduced. Finally, the challenges and prospects of nanohemostasis are discussed.

5.
Neuropharmacology ; : 107843, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31704273

RESUMO

Alzheimer's disease (AD), the most common form of dementia, still lacks effective treatment at present. Alpha-asarone (ASA) is the major compound isolated from the Chinese medicinal herb Acorus gramineus. It has been reported to enhance cognitive function in rodent models, yet its mechanism was not fully understood. In this work, we demonstrated that ASA improved the spatial memory, reduced the neuronal injury, and decreased the level of Aß1-42 in the hippocampus of aged rats. The results also showed that ASA had the neuroprotective effects against glutamate toxicity and decreased cytoplasmic calcium level in primary hippocampal neurons. By comparing the multiple properties of ASA and propofol (PPF) via computer modelling, we speculated that ASA may bind to the PPF binding site of type A gamma (γ)-aminobutyric acid receptors (GABAARs). This was further supported by the whole-cell patch-clamp recording. Our results suggested that ASA, as a GABAAR positive allosteric modulator (PAM), can improve cognitive function of aged rats by alleviating the neuronal overexcitation. Furthermore, the binding mode of ASA on GABAAR may lay a foundation for structure-based drug design in AD therapy.

6.
Anal Chem ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670502

RESUMO

Förster resonance energy transfer (FRET) is a well-established method for studying macromolecular interactions and con-formational changes within proteins. Such a method normally uses fluorescent proteins or chemical labeling methods which are often only accessible to surface exposed residues and risk disturbing target protein structures. Here, we demonstrate that the genetic incorporation of a synthetic fluorescent amino acid, L-(7-hydroxycoumarin-4-yl) ethylglycine (Cou), and natural endogenous fluorophore Tryptophan (Trp) residues of a protein, could serve as an efficient FRET pair to monitor protein interactions, using the signaling transducer ß-arrestin-1 as a model system. We used this technology to record the dynamic spectra in both binding and competition experiments of ß-arrestin-1, the contribution of each specific phosphate in ternary complex formation, in a rapid and efficient manner. The determined Kd value for the association between the active arres-tin and Fab30 is 0.68 µM in the three components interaction system. Moreover, we were able to determine the contributions of the site 3 phospho-site and the site 6 phospho-site binding each contributed to the high affinity ternary complex assem-bling as 2.7 folds and 15.5 folds respectively, which were never determined before. These results thus highlighted the poten-tial usage of this new method in measurement of the allosteric induced enhanced affinity with small amount proteins and in a fast manner and in a complex system. Collectively, our newly developed Trp : Cou FRET system based on genetic expan-sion technology has extended the molecular toolboxes available for biochemical and structural biology studies.

7.
Mol Metab ; 29: 145-157, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31668386

RESUMO

OBJECTIVES: High fructose feeding changes fibroblast growth factor 21 (FGF21) regulation. Lactobacillus rhamnosus GG (LGG) supplementation reduces fructose-induced non-alcoholic fatty liver disease (NAFLD). The aim of this study was to determine the role of FGF21 and underlying mechanisms in the protective effects of LGG. METHODS: FGF21 knockout (KO) mice and C57BL/6 wild type (WT) mice were fed 30% fructose for 12 weeks. LGG was administered to the mice in the last 4 weeks during fructose feeding. FGF21-adiponectin (ADPN)-mediated hepatic lipogenesis and inflammation were investigated. RESULTS: FGF21 expression was robustly increased after 5-weeks of feeding and significantly decreased after 12-weeks of feeding in fructose-induced NAFLD mice. LGG administration reversed the depressed FGF21 expression, increased adipose production of ADPN, and reduced hepatic fat accumulation and inflammation in the WT mice but not in the KO mice. Hepatic nuclear carbohydrate responsive-element binding protein (ChREBP) was increased by fructose and reduced by LGG, resulting in a reduction in the expression of lipogenic genes. The methylated form of protein phosphatase 2A (PP2A) C, which dephosphorylates and activates ChREBP, was upregulated by fructose and normalized by LGG. Leucine carboxyl methyltransferase-1, which methylates PP2AC, was also increased by fructose and decreased by LGG. However, those beneficial effects of LGG were blunted in the KO mice. Hepatic dihydrosphingosine-1-phosphate, which inhibits PP2A, was markedly increased by LGG in the WT mice but attenuated in the KO mice. LGG decreased adipose hypertrophy and increased serum levels of ADPN, which regulates sphingosine metabolism. This beneficial effect was decreased in the KO mice. CONCLUSION: LGG administration increases hepatic FGF21 expression and serum ADPN concentration, resulting in a reduced ChREBP activation through dihydrosphingosine-1-phosphate-mediated PP2A deactivation, and subsequently reversed fructose-induced NAFLD. Thus, our data suggest that FGF21 is required for the beneficial effects of LGG in reversal of fructose-induced NAFLD.

8.
Genome Med ; 11(1): 67, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31666118

RESUMO

BACKGROUND: Cancer neoantigens are expressed only in cancer cells and presented on the tumor cell surface in complex with major histocompatibility complex (MHC) class I proteins for recognition by cytotoxic T cells. Accurate and rapid identification of neoantigens play a pivotal role in cancer immunotherapy. Although several in silico tools for neoantigen prediction have been presented, limitations of these tools exist. RESULTS: We developed pTuneos, a computational pipeline for prioritizing tumor neoantigens from next-generation sequencing data. We tested the performance of pTuneos on the melanoma cancer vaccine cohort data and tumor-infiltrating lymphocyte (TIL)-recognized neopeptide data. pTuneos is able to predict the MHC presentation and T cell recognition ability of the candidate neoantigens, and the actual immunogenicity of single-nucleotide variant (SNV)-based neopeptides considering their natural processing and presentation, surpassing the existing tools with a comprehensive and quantitative benchmark of their neoantigen prioritization performance and running time. pTuneos was further tested on The Cancer Genome Atlas (TCGA) cohort data as well as the melanoma and non-small cell lung cancer (NSCLC) cohort data undergoing checkpoint blockade immunotherapy. The overall neoantigen immunogenicity score proposed by pTuneos is demonstrated to be a powerful and pan-cancer marker for survival prediction compared to traditional well-established biomarkers. CONCLUSIONS: In summary, pTuneos provides the state-of-the-art one-stop and user-friendly solution for prioritizing SNV-based candidate neoepitopes, which could help to advance research on next-generation cancer immunotherapies and personalized cancer vaccines. pTuneos is available at https://github.com/bm2-lab/pTuneos , with a Docker version for quick deployment at https://cloud.docker.com/u/bm2lab/repository/docker/bm2lab/ptuneos .

9.
iScience ; 21: 249-260, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31677477

RESUMO

Compared with SNV&indel-based neoantigens, fusion-based neoantigens are not well characterized. In the present study, we performed a comprehensive analysis of the landscape of tumor fusion neoantigens in cancer and proposed a score scheme to quantitatively assess their immunogenic potentials. By analyzing three large-scale tumor datasets, we demonstrated that (1) the tumor fusion candidate neoantigen burden is not related to the immunotherapy outcome; (2) fusion neoantigens tend to have notably higher immunogenic potentials than SNV&indel-based candidate neoantigens, making them better candidates for cancer vaccines; (3) fusion candidate neoantigens distribute sparsely between individual patients. Although several recurrent candidate neoantigens exist, they usually have extremely low immunogenic potentials, suggesting that vaccination-based cancer immunotherapy must be personalized; (4) compared with fusion mutations involving tumor passenger genes, fusion mutations involving oncogenic genes have remarkably low immunogenic potentials, indicating that they undergo selection pressure during tumorigenesis.

10.
Theranostics ; 9(25): 7566-7582, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695787

RESUMO

Liver fibrosis leading to cirrhosis is one of the major health burdens worldwide with currently limited therapeutic options available. Long noncoding RNAs (lncRNAs) play important roles in various biological and pathological processes in a cell- or tissue-specific manner. However, there is still an important gap in the understanding of the role of hepatocyte-specific lncRNAs in liver fibrosis. Methods: The expressions of lnc-Hser in human and mice fibrotic livers as well as primary hepatocytes (HCs) of mice developing liver fibrosis were determined by real-time RT-PCR. The roles and mechanisms of lnc-Hser in HCs and liver fibrosis were determined in vitro and in vivo. Results: In this study, we have identified a hepatocyte-specifically expressed lnc-Hser, which was reduced in human and mice fibrotic livers as well as primary HCs of mice developing liver fibrosis. We have shown that silencing lnc-Hser aggravated liver fibrosis both in vitro and in vivo through inducing the epithelial-mesenchymal transition (EMT) and the apoptosis of HCs. In addition, knockdown of lnc-Hser promoted hepatic stellate cells (HSCs) activation through the signals derived from injured HCs. Mechanistically, we have revealed that lnc-Hser inhibited HCs apoptosis via the C5AR1-Hippo-YAP pathway and suppressed HCs EMT via the Notch signaling. Conclusions: Our work has identified a hepatocyte-specific lnc-HSER that regulates liver fibrosis, providing a proof that this molecule is a novel biomarker for damaged HCs and a potential target for anti-fibrotic therapy.

11.
PLoS Comput Biol ; 15(10): e1007343, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31671086

RESUMO

Adopting a systems approach, we devise a general workflow to define actionable subtypes in human cancers. Applied to small cell lung cancer (SCLC), the workflow identifies four subtypes based on global gene expression patterns and ontologies. Three correspond to known subtypes (SCLC-A, SCLC-N, and SCLC-Y), while the fourth is a previously undescribed ASCL1+ neuroendocrine variant (NEv2, or SCLC-A2). Tumor deconvolution with subtype gene signatures shows that all of the subtypes are detectable in varying proportions in human and mouse tumors. To understand how multiple stable subtypes can arise within a tumor, we infer a network of transcription factors and develop BooleaBayes, a minimally-constrained Boolean rule-fitting approach. In silico perturbations of the network identify master regulators and destabilizers of its attractors. Specific to NEv2, BooleaBayes predicts ELF3 and NR0B1 as master regulators of the subtype, and TCF3 as a master destabilizer. Since the four subtypes exhibit differential drug sensitivity, with NEv2 consistently least sensitive, these findings may lead to actionable therapeutic strategies that consider SCLC intratumoral heterogeneity. Our systems-level approach should generalize to other cancer types.

12.
Nucleic Acids Res ; 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31586401

RESUMO

Histone deacetylase 3 (Hdac3) is a target of the FDA approved HDAC inhibitors, which are used for the treatment of lymphoid malignancies. Here, we used Cd19-Cre to conditionally delete Hdac3 to define its role in germinal center B cells, which represent the cell of origin for many B cell malignancies. Cd19-Cre-Hdac3-/- mice showed impaired germinal center formation along with a defect in plasmablast production. Analysis of Hdac3-/- germinal centers revealed a reduction in dark zone centroblasts and accumulation of light zone centrocytes. RNA-seq revealed a significant correlation between genes up-regulated upon Hdac3 loss and those up-regulated in Foxo1-deleted germinal center B cells, even though Foxo1 typically activates transcription. Therefore, to determine whether gene expression changes observed in Hdac3-/- germinal centers were a result of direct effects of Hdac3 deacetylase activity, we used an HDAC3 selective inhibitor and examined nascent transcription in germinal center-derived cell lines. Transcriptional changes upon HDAC3 inhibition were enriched for light zone gene signatures as observed in germinal centers. Further comparison of PRO-seq data with ChIP-seq/exo data for BCL6, SMRT, FOXO1 and H3K27ac identified direct targets of HDAC3 function including CD86, CD83 and CXCR5 that are likely responsible for driving the light zone phenotype observed in vivo.

13.
J Cell Biochem ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31571264

RESUMO

Acute coronary syndrome (ACS) is characterized by atherosclerotic plaque rupture with a high incidence of recurrent ischemic events. Several microRNAs are found to be aberrantly expressed in atherosclerotic plaques. This study aims to investigate the effects of microRNA-9 (miR-9) on vulnerable atherosclerotic plaque and vascular remodeling in ACS and underlying mechanisms. Microarray-based gene expression profiling was used to identify differentially expressed genes related to ACS and regulatory miRNAs. Oxidized low-density lipoprotein (lectin-like) receptor 1 (OLR1) was identified to be aberrantly activated in ACS and regulated by miR-9. OLR1 was verified as a target gene of miR-9 by bioinformatics prediction and dual luciferase reporter gene assay. The atherosclerotic models were induced in ApoE-/- mice, in which the agomir or antagomir of miR-9, or small interfering RNA (siRNA) against OLR1 were separately introduced. Serum lipid levels and expression of vascular remodeling and inflammatory response-related factors were determined, respectively. On the basis of the obtained results, in the atherosclerosis mice treated with the agomir of miR-9 and siRNA against OLR1, the p38-mitogen-activated protein kinase (p38MAPK) pathway was inhibited; levels of triglyceride, total cholesterol, low-density lipoprotein cholesterol, tumor necrosis factor-α, interleukin-6, and vascular endothelial growth factor were reduced, but the high-density lipoprotein cholesterol level was increased, along with decreased vulnerable atherosclerotic plaque area and enhanced vascular remodeling. Taken together, these findings suggested an inhibitory role miR-9 acts in the formation of vulnerable atherosclerotic plaques in ACS mice, along with a promoted vascular remodeling, via a negative feedback regulation of OLR1-mediated p38MAPK pathway.

14.
Nano Lett ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31593471

RESUMO

Tumor heterogeneity has been one of the most important factors leading to the failure of conventional cancer therapies due to the accumulation of genetically distinct tumor-cell subpopulations during the tumor development process. Due to the diversity of genetic mutations during tumor growth, combining the use of multiple drugs has only achieved limited success in combating heterogeneous tumors. Herein, we report a novel antitumor strategy that effectively addresses tumor heterogeneity by using a CRISPR/Cas9-based nanoRNP carrying a combination of sgRNAs. Such nanoRNP is synthesized from Cas9 ribonucleoprotein, any combinations of required sgRNAs, and a rationally designed responsive polymer that endows nanoRNP with high circulating stability, enhanced tumor accumulation, and the efficient gene editing in targeted tumor cells eventually. By carrying a combination of sgRNAs that targets STAT3 and RUNX1, the nanoRNP exhibited efficient gene expression disruptions on a heterogeneous tumor model with two subsets of cells whose proliferations were sensitive to the reduced expression of STAT3 and RUNX1, respectively, leading to the effective growth inhibition of the heterogeneous tumor. Considering the close relationship between tumor heterogeneity and cancer progression, resistance to therapy, and recurrences, nanoRNP provides a feasible strategy to overcome tumor heterogeneity in the development of more advanced cancer therapy against malignant tumors.

15.
ChemSusChem ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31646763

RESUMO

The utilization of active sites and reaction kinetics of MoS 2 anodes for sodium ion batteries (SIBs) are highly related with the phase components (IT and 2H phases) and electrode architecture. In this work, we design and fabricate wrinkled 1T-MoSe 2 nanoflakes anchored on highly conductive TiC/C nanorods forming 1T-MoSe 2 @TiC/C branch-core arrays by a powerful chemical vapor deposition (CVD)-solvothermal method. Furthermore, 1T-MoSe 2 branch can be easily transformed into 2H-MoSe 2 counterpart after a facile annealing process. As compared to 2H-MoSe 2 , 1T-MoSe 2 shows larger interlayer spacing and higher electronic conductivity, which are beneficial for the acceleration of reaction kinetics and capacity improvement. In addition, direct growth of 1T-MoSe 2 nanoflakes on TiC/C skeleton could not only enhance the electrical conductivity, but also contribute to reinforced structural stability. Accordingly, 1T-MoSe 2 @TiC/C branch-core arrays are demonstrated with higher capacity and better rate performance (184 mA h g -1 at 10 A g -1 ) and impressive durability over 500 cycles with a capacity retention of ~91.8%. Such a phase modulation plus branch-core design provides a general way for synthesis of other high-performance electrode materials for applications in electrochemical energy storage.

16.
J Natl Cancer Inst ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31647544

RESUMO

BACKGROUND: We aimed to systematically evaluate telomere dynamics across a spectrum of pediatric cancers, search for underlying molecular mechanisms, and assess potential prognostic value. METHODS: The fraction of telomeric reads was determined from whole-genome sequencing data for paired tumor/normal samples from 653 patients with 23 cancer types from the Pediatric Cancer Genome Project (PCGP). Telomere dynamics were characterized as the ratio of telomere fractions between tumor and normal samples. Somatic mutations were gathered, RNA sequencing data for 330 patients were analyzed for gene expression, and Cox regression was used to assess the telomere dynamics on patient survival. RESULTS: Telomere lengthening was observed in 28.7% of solid tumors, 10.5% of brain tumors, and 4.3% of hematological cancers. Among 81 samples with telomere lengthening, 26 had somatic mutations in ATRX, corroborated by a low level of ATRX expression in the subset of tumors with RNA sequencing. TERT amplification and/or activation was observed in 10 tumors with telomere lengthening, including 2 leukemias of the E2A-PBX1 subtype. Among hematological cancers, pathway analysis for genes with expressions most negatively correlated with telomere fractions suggest implication of a gene ontology process of antigen presentation by MHC class II. A higher ratio of telomere fractions was statistically significantly associated with poorer survival for patients with brain tumors (hazard ratio = 2.18, 95% confidence interval = 1.37 to 3.46). CONCLUSION: Because telomerase inhibitors are currently being explored as potential agents to treat pediatric cancer, these data are valuable as they identify a subpopulation of patients with reactivation of telomerase who are most likely to benefit from this novel therapeutic option.

17.
J Therm Biol ; 85: 102420, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31657761

RESUMO

The purpose of the current study was to investigate that effect of duration of thermal stress on growth performance, oxidative stress indices in serum, the expression and localization of ABCG2, and mitochondria ROS production in skeletal muscle, small intestine and immune organs, and then to further reveal correlations between indicators. At 28 days of age, sixty broilers were randomly divided into the control group (25 ±â€¯2 °C; 24 h/day) and the heat stress group (36 ±â€¯2 °C; 8 h/day lasted for 1 week or 2 weeks). Fifteen broilers per group were respectively euthanized, and some samples were respectively collected from the control and the heat stress groups at the end of the 1st week or the 2nd week of heat stress. A typical heat stress response has been observed at this temperature. Compared with the control group, the birds subjected to heat stress at the end of the 1st week reduced (P < 0.05) body weight (BW), average daily feed intake (ADFI), average daily gain (ADG), the activity of serum antioxidant enzyme and content of glutathione (GSH), while increased (P < 0.05) feed conversion ratio (FCR), serum corticosterone and malondialdehyde (MDA) levels. However, when the heat stress lasted for the end of the 2nd week, there was no significant difference (P > 0.05) in ADFI, ADG, FCR and serum contents of corticosterone, MDA and GSH. Regardless of duration of thermal stress, the localization of ABCG2 protein had no change. Moreover, heat stress also did not affect (P > 0.05) the IOD of the ABCG2 positive portion and the expression of the ABCG2 mRNA in the pectorales, crureus, duodenum, jejunum, ileum and spleen, while significantly increased (P < 0.05) the corresponding tissues ROS production at the end of the 1st week of heat stress. In contrast, at the end of the 2nd week of heat stress, IOD of the ABCG2 positive portion and the expression of the ABCG2 mRNA in heat stress group significantly increased (P < 0.05), while the corresponding tissues ROS production had no difference (P > 0.05) compared to the control group. Collectively, duration of thermal stress affects growth performance, serum oxidative stress indices, and the expression of ABCG2 and the ROS production of broiler tissues in a time-dependent manner. There is a negative correlation between the expression of ABCG2 and the ROS production in the corresponding tissues under heat stress.

18.
J Pharmacol Sci ; 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31640920

RESUMO

Pulmonary arterial hypertension (PAH) is defined as elevation of mean pulmonary arterial pressure to ≥25 mmHg within the low pressure pulmonary circulatory system. PAH is characterized by obstructive vascular remodeling, partially due to excessive pulmonary arterial smooth muscle cell (PASMC) proliferation. Puerarin is a natural flavonoid isolated from the herb Radix puerariae, which has been widely used for the treatment of cardiovascular and cerebrovascular disorders and diabetes. However, how puerarin mediates autophagy in the progression of pulmonary vascular remodeling is unclear. In this study, we explored the effects of puerarin in a hypoxic pulmonary hypertension (PH) rat model using immunohistochemistry, and morphometric analyses of right ventricle. In addition, cell counting kit 8 assay, western blotting and flow cytometry were employed to test cell proliferation in PASMCs, and then autophagy was tested with mRFP-GFP-LC3 fluorescence microscopy and Western blot. We found that puerarin could alleviate hypoxia-induced PH in rats and improved pulmonary histopathology, and also reduced the expression of autophagy markers in vivo and in vitro. Moreover, puerarin also ameliorated hypoxia-induced PASMC proliferation in an autophagy-dependent manner. Overall, these findings demonstrated that puerarin could prevent hypoxia-induced PH in rats, possibly via reducing autophagy and suppressing cell proliferation.

19.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(5): 785-794, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-31631627

RESUMO

The purpose of this paper was to investigate the effects of wearable lower limb exoskeletons on the kinematics and kinetic parameters of the lower extremity joints and muscles during normal walking, aiming to provide scientific basis for optimizing its structural design and improving its system performance. We collected the walking data of subjects without lower limb exoskeleton and selected the joint angles in sagittal plane of human lower limbs as driving data for lower limb exoskeleton simulation analysis. Anybody (the human biomechanical analysis software) was used to establish the human body model (the human body model without lower limb exoskeleton) and the man-machine system model (the lower limb exoskeleton model). The kinematics parameters (joint force and joint moment) and muscle parameters (muscle strength, muscle activation, muscle contraction velocity and muscle length) under two situations were compared. The experimental result shows that walking gait after wearing the lower limb exoskeleton meets the normal gait, but there would be an occasional and sudden increase in muscle strength. The max activation level of main lower limb muscles were all not exceeding 1, in another word the muscles did not appear fatigue and injury. The highest increase activation level occurred in rectus femoris (0.456), and the lowest increase activation level occurred in semitendinosus (0.013), which means the lower limb exoskeletons could lead to the fatigue and injury of semitendinosus. The results of this study illustrate that to avoid the phenomenon of sudden increase of individual muscle force, the consistency between the length of body segment and the length of exoskeleton rod should be considered in the design of lower limb exoskeleton extremity.


Assuntos
Exoesqueleto Energizado , Marcha , Extremidade Inferior/fisiologia , Fenômenos Biomecânicos , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-31645098

RESUMO

Although strategies for smart control of droplets by utilizing slippery surfaces that are typically made by infusing lubricants into porous surfaces are booming, no surface can smartly control the start or stop of droplet sliding without external environmental stimuli. A strategy for how surfaces alone, if constituted by lubricant-infused porous hydrophobic sticky surfaces (LIPHSS) with a specific interface self-adjusting system, can achieve the target of smart control of a drop's slide is presented here. The continuous self-adjustment of the interface formed by droplets and LIPHSS leads to the occurrence of droplet sinking behavior. The droplet's sinking reduces its sliding angle (SA) and thus can trigger the sliding of the droplet deposited on LIPHSS with a tilt base angle between the SA after sinking and the SA before sinking. Furthermore, regulating lubricant layer thickness and tilt base angle is an important way to achieve smart control of the time required to initiate the sliding of the droplet. The uniqueness of the study is focused on the clever extension of the sinking behavior of droplets on LIPHSS to achieve a programmable time delay switch to smart control the sliding of droplets.

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