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1.
Nat Commun ; 11(1): 688, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019936

RESUMO

High-resolution structures have not been reported for replicative helicases at a replication fork at atomic resolution, a prerequisite to understanding the unwinding mechanism. The eukaryotic replicative CMG (Cdc45, Mcm2-7, GINS) helicase contains a Mcm2-7 motor ring, with the N-tier ring in front and the C-tier motor ring behind. The N-tier ring is structurally divided into a zinc finger (ZF) sub-ring followed by the oligosaccharide/oligonucleotide-binding (OB) fold ring. Here we report the cryo-EM structure of CMG on forked DNA at 3.9 Å, revealing that parental DNA enters the ZF sub-ring and strand separation occurs at the bottom of the ZF sub-ring, where the lagging strand is blocked and diverted sideways by OB hairpin-loops of Mcm3, Mcm4, Mcm6, and Mcm7. Thus, instead of employing a specific steric exclusion process, or even a separation pin, unwinding is achieved via a "dam-and-diversion tunnel" mechanism that does not require specific protein-DNA interaction. The C-tier motor ring contains spirally configured PS1 and H2I loops of Mcms 2, 3, 5, 6 that translocate on the spirally-configured leading strand, and thereby pull the preceding DNA segment through the diversion tunnel for strand separation.

2.
Oncol Rep ; 43(4): 1338-1348, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32020224

RESUMO

DEK has been revealed to be overexpressed in many cancers and associated with cancer progression. The aim of the present study was to elucidate the role of DEK with a specific focus on its underlying mechanism in lung cancers. DEK expression in lung cancers and normal lung tissues and the correlations between DEK expression and clinicopathological parameters of lung cancers were investigated using the data from The Cancer Genome Atlas (TCGA). DEK expression was upregulated by DEK transfection or downregulated by DEK shRNA interference in A549 and H1299 cells. The effects of DEK on the Wnt signaling pathway and epithelial­mesenchymal transition (EMT) were examined using western blotting. Proliferative and invasive abilities were observed in A549 and H1299 cells treated with DEK using an MTT assay, colony formation assay, and Transwell migration and invasion assays. The expression of DEK was higher in lung cancer tissues than that in normal lung tissues. DEK expression was positively correlated with the expression of epidermal growth factor receptor (EGFR) and KRAS in lung adenocarcinomas. High expression of DEK indicated poor prognosis in lung adenocarcinomas (P=0.018). Enhanced expression of DEK upregulated the levels of active­ß­catenin and Wnt target genes, such as cyclin D1, c­Myc and MMP7 and increased the proliferative and invasive abilities of lung cancer cells. Enhanced expression of DEK in A549 and H1299 cells also increased the levels of EGFR, KRAS, vimentin, Snail, and N­cadherin, and decreased the level of E­cadherin. The opposite results were obtained with knockdown of DEK expression. DEK was highly expressed in lung cancers and indicated poor prognosis in lung adenocarcinomas. DEK expression activated the Wnt signaling pathway and EMT process and promoted the proliferation and invasion of lung cancers.

3.
Environ Toxicol Pharmacol ; 76: 103350, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32058320

RESUMO

Lead (Pb) is recognized as a potent inducer of synaptic toxicity generally associated with reduced synaptic transmission and increased neuronal fiber excitability, becoming an environmental risk for neurodegenerative processes. Despite numerous toxicological studies on Pb have been directed to the developing brain, attention concerning long-term consequences of pubertal chronic Pb exposure on neuronal activity is still lacking. Thus, we exposed 4-week-old male mice to 0.2 % lead acetate solution for one month, then, conducted behavioral tests or extracted brain homogenate from mice prefrontal cortex (PFC) and hippocampus at the age of 4, 13 and 16-month-old respectively. Our results showed that treated mice exhibited an evident increase in latency to reach platform following pubertal Pb exposure and aging. The increase of 8-OHdG revealed evident neural DNA oxidative damage across time upon pubertal Pb exposure. In the hippocampus of lead exposed mice at three age nodes, the expression of brain-derived neurotrophic factor precursor (proBDNF) increased, while that of mature BDNF (mBDNF), cAMP-response element binding protein (CREB) and phosphorylated CREB (pCREB) decreased compared with the control group. Furthermore, the expression of BACE1 protein and tau phosphorylation level in PFC and hippocampus increased, APP mRNAs in PFC and prolonged induction of BACE1 in hippocampus. Our results show that chronic Pb exposure from pubertal stage onward can either initiate divergent synaptic-related gene expression patterns in adulthood or trigger time-course of neurodegenerative profile within the PFC or hippocampus, which can contribute consistent deficits of cognition across subsequent age-nodes.

4.
ACS Nano ; 14(2): 1468-1481, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31939662

RESUMO

Radiotherapy remains a major treatment modality for cancer types such as non-small cell lung carcinoma (or NSCLC). To enhance treatment efficacy at a given radiation dose, radiosensitizers are often used during radiotherapy. Herein, we report a nanoparticle agent that can selectively sensitize cancer cells to radiotherapy. Specifically, we nitrosylated maytansinoid DM1 and then loaded the resulting prodrug, DM1-NO, onto poly(lactide-co-glycolic)-block-poly(ethylene glycol) (PLGA-b-PEG) nanoparticles. The toxicity of DM1 is suppressed by nanoparticle encapsulation and nitrosylation, allowing the drug to be delivered to tumors through the enhanced permeability and retention effect. Under irradiation to tumors, the oxidative stress is elevated, leading to the cleavage of the S-N bond and the release of DM1 and nitric oxide (NO). DM1 inhibits microtubule polymerization and enriches cells at the G2/M phase, which is more radiosensitive. NO under irradiation forms highly toxic radicals such as peroxynitrites, which also contribute to tumor suppression. The two components work synergistically to enhance radiotherapy outcomes, which was confirmed in vitro by clonogenic assays and in vivo with H1299 tumor-bearing mice. Our studies suggest the great promise of DM1-NO PLGA nanoparticles in enhancing radiotherapy against NSCLC and potentially other tumor types.

5.
Nat Mater ; 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932669

RESUMO

The ability to organize nanoscale objects into well-defined three-dimensional (3D) arrays can translate advances in nanoscale synthesis into targeted material fabrication. Despite successes in nanoparticle assembly, most extant methods are system specific and not fully compatible with biomolecules. Here, we report a platform for creating distinct 3D ordered arrays from different nanomaterials using DNA-prescribed and valence-controlled material voxels. These material voxels consist of 3D DNA frames that integrate nano-objects within their scaffold, thus enabling the object's valence and coordination to be determined by the frame's vertices, which can bind to each other through hybridization. Such DNA material voxels define the lattice symmetry through the spatially prescribed valence decoupling the 3D assembly process from the nature of the nanocomponents, such as their intrinsic properties and shapes. We show this by assembling metallic and semiconductor nanoparticles and also protein superlattices. We support the technological potential of such an assembly approach by fabricating light-emitting 3D arrays with diffraction-limited spectral purity and 3D enzymatic arrays with increased activity.

6.
Gen Comp Endocrinol ; 286: 113303, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31654676

RESUMO

The importance of cyclic guanosine monophosphate (cGMP) signaling pathway in oocyte maturation has recently attracted much attention in vertebrates. Previously, using zebrafish as a model, we have revealed the role of cGMP and the action of cGMP protein kinase (PKG) in oocyte maturation. In the present study, the function of a cGMP specific phosphodiesterase (PDE5a) is further analyzed in oocyte maturation in zebrafish. Two distinct PDE5a coding genes (named PDE5aa and PDE5ab) were identified in zebrafish, and expressed in most adult tissues including ovary. Both pde5aa and pde5ab mRNA are predominantly expressed in the oocyte but not in follicular cells. Two commercial antibodies targeted to mammalian PDE5a and phosphorylated PDE5a were validated in zebrafish, and we found both antibodies can be used to detect PDE5ab and phosphorylated PDE5ab of zebrafish, respectively. Using both antibodies, we found PDE5ab is only expressed in the oocyte and the phosphorylation of PDE5ab in oocyte could be activated during oocyte maturation induced by human chronic gonadotropin. Intriguingly, we found that the oocyte maturation could be stimulated by treatment of either two different PDE5a inhibitors, sildenafil or tadalafil, and such effects could be completely blocked by a PKG inhibitor KT5823 and two gap junction blockers, respectively. All of these results clearly demonstrate the importance of PDE5a in maintaining the oocyte maturation of zebrafish. When compared with mammals, the functional model of PDE5a is different in zebrafish, suggesting the function of PDE5a might shift from the oocyte in fish to the granulosa cell in mammals during evolution.

7.
Eur J Anaesthesiol ; 37(2): 91-97, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31567592

RESUMO

BACKGROUND: The modified dynamic needle tip positioning (MDNTP) technique for ultrasound-guided radial artery cannulation (MDNTP-US technique) in neonates can be technically challenging for trainee anaesthesiologists. We hypothesised that by associating the MDNTP-US technique with hypodermic 0.9% sodium chloride (Saline MDNTP-US technique), which increases the subcutaneous radial artery depth, the procedure would become easier for trainee anaesthesiologists. OBJECTIVE: To compare the Saline MDNTP-US technique, with the MDNTP-US technique for radial artery catheterisation in neonates by trainee anaesthesiologists with limited experience. DESIGN: Randomised controlled trial. PATIENTS: Ninety-six neonates scheduled to undergo major abdominal surgery requiring continuous arterial pressure monitoring between May 2018 and December 2018 at the Children's Hospital of Chongqing Medical University were enrolled. Neonates with signs of skin erosions or haematomas at or near the insertion site, as well as those with low noninvasive blood pressure values, were excluded. INTERVENTION: Neonates were randomised to the Saline MDNTP-US and MDNTP-US groups in a 1 : 1 ratio. Twelve trainees performed the cannulation procedures. MAIN OUTCOME MEASURES: Duration of procedure, first attempt success rate, rate of success within 10 min, and the incidence of haematoma and thrombosis. RESULTS: The median [IQR] time to perform cannulation was less for the Saline MDNTP-US technique than for the MDNTP-US technique: 203 [160 to 600] vs. 600 s [220 to 600]; P = 0.005. The rate of success within 10 min, 72.9 vs. 47.9%; P = 0.012, was higher in the Saline MDNTP-US group than in the MDNTP-US group. The incidence of haematoma on postoperative day 1 was lower in the Saline MDNTP-US group than in the MDNTP-US group: 8.3 vs. 22.9%; P = 0.049. CONCLUSION: Trainee anaesthesiologists can achieve higher success rates by using the Saline MDNTP-US technique instead of the MDNTP-US technique for radial artery catheterisation in neonates, taking less time with a lower incidence of complications. TRIAL REGISTRATION: ChiCTR-IOR-17014119 (Chinese Clinical Trial Registry).

8.
Food Chem ; 308: 125707, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669943

RESUMO

The ripening of the apple (Malus × domestica Borkh.) fruit is regulated by the phytohormone ethylene, where degreening is an important physiological metabolism caused by chlorophyll (Chl) degradation. However, to date, research on how ethylene affects the Chl degradation pathway of apple peel during ripening remains scarce. In this study, the effects of ethylene on the expression of Chl catabolic genes (CCGs) of apple peel during ripening were studied by treating harvested commercial mature apples with 0.5 µL L-1 1-methylcyclopropene (1-MCP). The results showed that 1-MCP treatment led to a delayed climacteric peak of respiration and ethylene production, exhibiting higher Chl content and hue angle (H˚) compared to untreated fruit during ripening. Lower quantities of pheophorbide a oxygenase (PAO), pheophytinase (PPH) and red Chl catabolite reductase (RCCR) were also observed in peel tissues under 1-MCP treatment during ripening. Further study with quantitative real-time polymerase chain reaction (qPCR) revealed that the expression of CCGs, except for MdNYE1a, increased atdifferentdegrees upon ripening. Meanwhile, the apples treated with 1-MCP presented a downregulated expression of MdRCCR2, MdNYC1, MdNYC3 and MdNOL2 and a fluctuating expression of MdNYE1a, MdPPH1, MdPAO6, MdPAO8 and MdHCAR compared with the controls during ripening. Our results indicated the regulatory role of ethylene in the Chl degradation pathway of apple peel during ripening.


Assuntos
Clorofila/metabolismo , Ciclopropanos/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Malus/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Etilenos/metabolismo , Armazenamento de Alimentos , Frutas/efeitos dos fármacos , Frutas/metabolismo , Malus/efeitos dos fármacos , Proteínas de Plantas/metabolismo
9.
Animals (Basel) ; 9(12)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31817035

RESUMO

The carcass and meat quality traits of pig breeds living at three different altitudes (Yorkshire pigs, YP: 500m; Qingyu Pigs, QYP: 1500m; Tibetan pigs, TP: 2500m) were compared. It was observed that there are obvious differences in pig breeds with respect to performance parameters. Specifically, YP had the best carcass traits, showing high slaughter rates and leanest meat. Conversely, QYP had the highest back fat thickness and intramuscular fat (IMF) content. For the high-altitude breed TP, the animals exhibited low L* and high a* values. The genotypes contributing to the observed phenotypes were supported by a PCR analysis. The glycolytic genes expression (HK, PFK, PK) were highest in YP, whereas expression of genes related to adipogenesis (C/EBPα, FABP4, SCD1) were highest in QYP. As expected, genes associated with angiogenesis and hypoxia (HIF1a, VEGFA) were expressed at the highest levels in TP. The composition and proportion of amino and fatty acids in pig muscles at the three altitudes examined also varied substantially. Among the breeds, TP had the highest proportion of umami amino acids, whereas QYP had the highest proportion of sweet amino acids. However, TP also exhibited the highest proportion of essential fatty acids and the lowest proportion of n6:n3. This study explains the high-altitude adaptive evolution and the formation of meat quality differences in different altitude pigs from various angles and provides a reference for local pork food processing and genetic improvement of local pigs.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31583908

RESUMO

Cerebral infarction is a leading cause of death, which calls for effective prevention and treatment. Transplant of neural stem cells (NSCs) is a potential therapeutic treatment to cerebral infarction although its efficacy still needs to be improved. Overexpression of Hypoxia-inducible factor 1α (HIF-1α) has been shown to enhance the protective effects of stem cell transplant on cerebral infarction. The expression of HIF-1α is predicted to be regulated by miR-155-5p. Therefore, we regulated the expression of miR-155-5p in NSCs and evaluated the effects of miR-155-5p-regulated NSC transplant on cerebral infarction. We inhibited miR-155-5p expression in NSCs by overexpressing miR-155-5p inhibitor. HIF-1α expression, cell viability and the expression of apoptosis markers were examined. We established the middle cerebral artery occlusion (MCAO) rat model, and the infarct volume, neurobehavioral outcomes, inflammation and oxidative stress were evaluated after NSC transplant. miR-155-5p directly targeted HIF-1α and negatively regulated its expression. Inhibition of miR-155-5p enhanced cell viability and prevented cell apoptosis. Transplant of miR-155-5p-inhibited NSCs significantly decreased infarct volume, improved neurobehavioral outcomes of MCAO rats. Transplant of miR-155-5p-inhibited NSCs significantly inhibited inflammation and oxidative stress. Inhibition of miR-155-5p in NSCs resulted in enhanced protection against cerebral infarction after NSC transplant.

11.
Elife ; 82019 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-31589141

RESUMO

The current view is that eukaryotic replisomes are independent. Here we show that Ctf4 tightly dimerizes CMG helicase, with an extensive interface involving Psf2, Cdc45, and Sld5. Interestingly, Ctf4 binds only one Pol α-primase. Thus, Ctf4 may have evolved as a trimer to organize two helicases and one Pol α-primase into a replication factory. In the 2CMG-Ctf43-1Pol α-primase factory model, the two CMGs nearly face each other, placing the two lagging strands toward the center and two leading strands out the sides. The single Pol α-primase is centrally located and may prime both sister replisomes. The Ctf4-coupled-sister replisome model is consistent with cellular microscopy studies revealing two sister forks of an origin remain attached and are pushed forward from a protein platform. The replication factory model may facilitate parental nucleosome transfer during replication.

12.
Hum Gene Ther Methods ; 30(5): 184-193, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31618139

RESUMO

Cerebral infarction is a leading cause of death, which calls for effective prevention and treatment. Transplant of neural stem cells (NSCs) is a potential therapeutic treatment to cerebral infarction although its efficacy still needs to be improved. Overexpression of hypoxia-inducible factor 1α (HIF-1α) has been shown to enhance the protective effects of stem cell transplant on cerebral infarction. The expression of HIF-1α is predicted to be regulated by miR-155-5p. Therefore, we regulated the expression of miR-155-5p in NSCs and evaluated the effects of miR-155-5p-regulated NSC transplant on cerebral infarction. We inhibited miR-155-5p expression in NSCs by overexpressing miR-155-5p inhibitor. HIF-1α expression, cell viability, and the expression of apoptosis markers were examined. We established the middle cerebral artery occlusion (MCAO) rat model, and the infarct volume, neurobehavioral outcomes, inflammation, and oxidative stress were evaluated after NSC transplant. miR-155-5p directly targeted HIF-1α and negatively regulated its expression. Inhibition of miR-155-5p enhanced cell viability and prevented cell apoptosis. Transplant of miR-155-5p-inhibited NSCs significantly decreased infarct volume and improved neurobehavioral outcomes of MCAO rats. Transplant of miR-155-5p-inhibited NSCs significantly inhibited inflammation and oxidative stress. Inhibition of miR-155-5p in NSCs resulted in enhanced protection against cerebral infarction after NSC transplant.

13.
Nat Commun ; 10(1): 4142, 2019 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515475

RESUMO

The heterodimeric eukaryotic Drs2p-Cdc50p complex is a lipid flippase that maintains cell membrane asymmetry. The enzyme complex exists in an autoinhibited form in the absence of an activator and is specifically activated by phosphatidylinositol-4-phosphate (PI4P), although the underlying mechanisms have been unclear. Here we report the cryo-EM structures of intact Drs2p-Cdc50p isolated from S. cerevisiae in apo form and in the PI4P-activated form at 2.8 Å and 3.3 Å resolution, respectively. The structures reveal that the Drs2p C-terminus lines a long groove in the cytosolic regulatory region to inhibit the flippase activity. PIP4 binding in a cytosol-proximal membrane region triggers a 90° rotation of a cytosolic helix switch that is located just upstream of the inhibitory C-terminal peptide. The rotation of the helix switch dislodges the C-terminus from the regulatory region, activating the flippase.


Assuntos
ATPases Transportadoras de Cálcio/antagonistas & inibidores , Lipídeos/química , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Saccharomyces cerevisiae/enzimologia , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , ATPases Transportadoras de Cálcio/química , ATPases Transportadoras de Cálcio/metabolismo , ATPases Transportadoras de Cálcio/ultraestrutura , Modelos Moleculares , Fosfatos de Fosfatidilinositol/metabolismo , Conformação Proteica , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/ultraestrutura , Especificidade por Substrato
14.
Molecules ; 24(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533306

RESUMO

Adipogenesis is a complex biological process and the main cause of obesity. Recently, microRNAs (miRNAs), a class of small endogenous non-coding RNAs, have been proven to play an important role in adipogenesis by the post-transcriptional regulation of target genes. In this current study, we observed an increment of miR-152 expression during the process of 3T3-L1 cell audiogenic differentiation. A functional analysis indicated that the overexpression of miR-152 inhibited pre-adipocyte proliferation and suppressed the expression of some cell cycle-related genes. Moreover, the overexpression of miR-152 promoted lipid accumulation in 3T3-L1 preadipocytes accompanied by increase of the expression of some pro-audiogenic genes. Additionally, a dual-luciferase reporter assay demonstrated lipoprotein lipase (LPL) was a direct target gene of miR-152 during preadipocyte differentiation. Further analysis showed that miR-152 was positively correlated with adipogenesis and intramuscular fat formation in vivo. Taken together, our findings suggest that miR-152 could suppress 3T3-L1 preadipocyte proliferation, whereas it could promote 3T3-L1 preadipocyte differentiation by negatively regulating LPL. The findings indicate that miR-152 might have a therapeutic significance for obesity and obesity-related metabolic syndrome.


Assuntos
Adipócitos/citologia , Adipócitos/metabolismo , Adipogenia/genética , Diferenciação Celular/genética , MicroRNAs/genética , Células 3T3-L1 , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Proliferação de Células , Células Cultivadas , Regulação da Expressão Gênica , Lipase Lipoproteica/genética , Camundongos , Modelos Biológicos , Interferência de RNA
15.
Biomed Res Int ; 2019: 3514574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534958

RESUMO

The immune system is involved in the development of diabetes complications and IgG Fc gamma receptors (FcgRs) are key immune receptors responsible for the effective control of both humoral and innate immunity. We investigated the effects of members of the FcgR superfamily into both the streptozotocin plus high fat-induced type 2 diabetes and high fat diet (HFD) models. FcgRIII-/- diabetic mice and FcgRIIb-/- diabetic mice had elevated levels of serum creatinine compared with wildtype (WT) diabetic mice. Renal histology of diabetic FcgRIII knockout and FcgRIIb knockout mice showed mesangial expansion and GBM thickening; the mechanistic study indicated a higher expression of TGF-ß1, TNF-α, and p-NFκB-p65 compared with wild type mouse. The HFD mouse with FcgRIII knockout or FcgRIIb knockout had increased biochemical and renal injury factors, but oxLDL deposition was higher than in FcgRIII-/- diabetic mice and FcgRIIb-/- diabetic mice. In vitro we further examined the mechanism by which the Fc gamma receptor promoted renal injury and transfected glomerular mesangial cells (GMCs) with FcgRI siRNA attenuated the level of TGF-ß1, TNF-α expression. In summary, FcgRI knockdown downregulated kidney inflammation and fibrosis and FcgRIIb knockout accelerated inflammation, fibrosis, and the anomalous deposition of oxLDL whereas FcgRIII deficiency failed to protect kidney from diabetic renal injury. These observations suggested that FcgRs might represent a novel target for the therapeutic intervention of diabetic nephropathy.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Receptores de IgG/deficiência , Animais , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/patologia , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Camundongos , Camundongos Knockout , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
16.
Environ Int ; 133(Pt A): 105142, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31513927

RESUMO

Frequent cyanobacterial blooms in the eutrophic waters produce a variety of toxins such as the monocyclic heptapeptide microcystins, greatly harming aquatic ecosystems and human health. However, little information of microcystins in agricultural fields is known. This field study of three common microcystin variants (MC-LR, MC-RR, and MC-YR) in vegetables (n = 161), soils (n = 161) and irrigation water samples (n = 23) collected from southern China regions affected by cyanobacteria blooms, shows their prevalence with total concentrations up to 514 µg/L water, 187 µg/kg soil (dry weight) and 382 µg/kg vegetable (fresh weight). MC-RR was the primary variant in all types of samples, accounting for 51.3-100% of total microcystin concentrations. Significant concentration-dependent correlations (p < 0.05) demonstrated that microcystin-contained irrigation waters were the major source of microcystin accumulation in both vegetables and soils. Meanwhile, intracellular-microcystins in irrigation water was found to play an important role in microcystins bioaccumulation in vegetables for the first time. Most vegetable samples (≥60%), particularly celery posed moderate or high human health risk via diet based on toxicity equivalents of the microcystins and reference dose for MC-LR (0.04 µg/kg/d), showing high food safety hidden dangers. Soil microcystins, especially MC-RR in 46.4-88.3% of soils could pose high ecological risks. This study highlights the potential high ecological and human health risks of microcystins in the real soil-vegetable systems of areas affected by cyanobacteria blooms, implying the profound significance and urgent need of investigation on microcystins in terrestrial ecosystems.

17.
Int J Biol Macromol ; 139: 1123-1132, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394150

RESUMO

Echinacea purpurea polysaccharide (EPP) was obtained by modern separation technology and sulfated EPP (sEPP) was prepared by sulfation modification. The immunological effects of EPP and sEPP were compared on chicken bone marrow-derived dendritic cells (chBM-DCs). The results showed that the surface marker expression of CD11c and CD80 was increased after chBM-DCs were cultured with three dosage of sEPP, especially in sEPPM group. Three dosage of sEPP, EPPL and LPS could significantly enhance the effects of chBM-DCs on the proliferation of allogenic mixed lymphocytes. After chBM-DCs treatment with EPP or sEPP in vitro, the levels of IL-2 of sEPPH and EPPM groups were significantly higher than those of LPS group (P < 0.05). All sEPP and EPP groups could enhance the level of IFN-γ and down-regulated the level of IL-4 and IL-10. Results indicated that both sEPP and EPP had immunoregulatory effects on chBM-DCs, sEPP possessed better immunoregulatory effects as compared with EPP.

18.
Front Genet ; 10: 670, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440271

RESUMO

Ventricular septal defect (VSD) is a fatal congenital heart disease showing severe consequence in affected infants. Early diagnosis plays an important role, particularly through genetic variants. Existing panel-based approaches of variants mining suffer from shortage of large panels, costly sequencing, and missing rare variants. Although a trio-based method alleviates these limitations to some extent, it is agnostic to novel mutations and computational intensive. Considering these limitations, we are studying a novel variants mining algorithm from trio-based sequencing data and apply it on a VSD trio to identify associated mutations. Our approach starts with irrelevant k-mer filtering from sequences of a trio via a newly conceived coupled Bloom Filter, then corrects sequencing errors by using a statistical approach and extends kept k-mers into long sequences. These extended sequences are used as input for variants needed. Later, the obtained variants are comprehensively analyzed against existing databases to mine VSD-related mutations. Experiments show that our trio-based algorithm narrows down candidate coding genes and lncRNAs by about 10- and 5-folds comparing with single sequence-based approaches, respectively. Meanwhile, our algorithm is 10 times faster and 2 magnitudes memory-frugal compared with existing state-of-the-art approach. By applying our approach to a VSD trio, we fish out an unreported gene-CD80, a combination of two genes-MYBPC3 and TRDN and a lncRNA-NONHSAT096266.2, which are highly likely to be VSD-related.

19.
Medicine (Baltimore) ; 98(35): e17008, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464958

RESUMO

Urinary kallidinogenase may assist recovery acute ischemic stroke. This study evaluated the effect of urinary kallidinogenase on National Institute of Health Stroke Scale (NIHSS) score, modified Rankin scale (mRS) score, and fasting glucose levels in patients with acute ischemic stroke (AIS) combined with diabetes mellitus and impaired fasting glucose.Patients with AIS and abnormal glucose metabolism were enrolled in this prospective cohort study and divided into 2 groups. The human urinary kallidinogenase (HUK) group were treated with urinary kallidinogenase and standard treatment; the control group received standard treatment. NIHSS scores, mRS scores, and fasting blood glucose were evaluated and compared.A total of 113 patients were included: 58 in the HUK group and 55 in the control group. NIHSS scores decreased with treatment in both groups (time effect P < .05), but were lower in the HUK group (main effect P = .026). The mRS score decreased in both groups from 10 until 90 days after treatment (time effect P < .05); the 2 groups were similar (main effect, P = .130). Blood glucose levels decreased in both groups 10 days after treatment (time effect, P < .05), but there was no significant treatment effect (main effect, P = .635). Multivariate analysis showed blood uric acid >420 µmol/L (odds ratio [OR]: 0.053, 95% confidence interval [CI]: 0.008-0.350; P = .002) and application of HUK (OR: 0.217, 95% CI: 0.049-0.954; P = .043) were associated with 90% NIHSS recovery. Baseline NIHSS score was independently associated with poor curative effect.Urinary kallidinogenase with conventional therapy significantly improved NIHSS scores in patients with AIS. Urinary kallidinogenase also showed a trend toward lower fasting blood glucose levels, although the level did not reach significance.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Calicreínas Teciduais/uso terapêutico , Adulto , Idoso , Glicemia/efeitos dos fármacos , Isquemia Encefálica/etiologia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/fisiopatologia , Feminino , Intolerância à Glucose/epidemiologia , Intolerância à Glucose/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Prospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia
20.
Biomed Pharmacother ; 118: 109298, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31404776

RESUMO

The long noncoding RNA myocardial infarction associated transcript (MIAT) was reported to be involved in the progression of multiple cancers. However, the exact roles and molecular mechanisms of MIAT in papillary thyroid cancer (PTC) progression are still unknown. We examined the expression levels of lncRNA MIAT in 50 paired PTC tissue specimens and four PTC cell lines by real time quantitative PCR (qRT-PCR). Cell counting kit 8, colony formation, wound healing and transwell assays were performed to examine the effect of MIAT on proliferation, colony formation, migration and invasion. Tumor xenograft models were created to detect the role of MIAT in vivo tumorigenesis. The target relationships were predicted by miRcode algorithm, and confirmed by dual luciferase reporter gene assay and qRT-PCR. We found that MIAT was up-regulated in PTC tissues and cell lines. High MIAT expression was positively associated with advanced tumor-node-metastasis (TNM) stage and lymph node metastasis. Functional assays showed that knockdown of MIAT in PTC cells significantly inhibited cell proliferation, colony formation, migration and invasion in vitro, as well as impaired tumor growth in vivo. Luciferase assays further confirmed that miR-212 interacts with MIAT. Additionally, the negatively correlation of miR-212 with MIAT was verified in patients' samples. Repression of miR-212 partly abrogated the inhibitory effects of MIAT knockdown on PTC cells. Taken together, these results indicated that MIAT might be an oncogenic lncRNA that promoted PTC progression, and might be a potential therapeutic target for PTC.


Assuntos
Progressão da Doença , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Animais , Sequência de Bases , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , RNA Longo não Codificante/genética , Ensaio Tumoral de Célula-Tronco , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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