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1.
Langmuir ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509705

RESUMO

Ion passage through ion-exchange membranes is vital in electrodialysis desalination, batteries and fuel cells, and water splitting. Simplified models of ion transport through such membranes frequently assume complete exclusion of coions (ions with the same sign of charge as the fixed charge in the membrane) from the membrane. However, a second assumption of constant counterion electrochemical potentials across the membrane leads to simple analytical expressions for ion fluxes and transmembrane potentials. Moreover, linear corrections to account for a small membrane electrical resistance yield analytical expressions with a wider applicability. For bi-ionic potential measurements and current-induced concentration polarization at low salt concentrations, these analytical solutions match the fluxes and potentials obtained numerically without the limiting assumptions. This gives confidence in both the limiting assumptions (under appropriate conditions) and the numerical solutions. At low ion concentrations, the analytical solutions may enable rapid characterization of membrane coatings or boundary layers in solution, and such boundary layers are important in many applications of ion-exchange membranes. In fact, the assumption of complete coion exclusion is sometimes more limiting than the constraint of constant electrochemical potentials of counterions across the membrane. Remarkably, this limiting case readily yields the ion accumulation and depletion regions above "ion-exchange patches" that reside beneath a solution with an applied electric field. Such regions are important for sample pre-concentration in microfluidic devices.

2.
J Food Biochem ; 43(8): e12944, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31368544

RESUMO

In recent years, probiotics have received increasing attention and become one type of popular functional food because of their many biological functions. Among these desirable biological functions, the immune regulation, antioxidative activities, and antimicrobial effects are essential properties to maintain host health. Probiotics can regulate the immune system and improve the antioxidative system by producing microbial components and metabolites. Meanwhile, probiotics also possess antimicrobial abilities owing to their competition for nutrient requirements and mucus adherence, reducing pathogenic toxins, producing antimicrobial metabolites (short-chain fatty acids, bacteriocins, reuterin, linoleic acid, and secondary bile acids) and enhancing intestinal, or systemic immunity. Therefore, probiotics could be used to alleviate heavy metal toxicity and metabolic disorders by improving immunity, the antioxidative system, and intestinal micro-environment. This comprehensive review mainly highlights the potential health promoting activities of probiotics based on their antioxidative, antimicrobial, and immune regulatory effects. PRACTICAL APPLICATIONS: The antioxidative defense and the immune system are essential to maintain human health. However, many factors may result in microbial dysbiosis in the gut, which subsequently leads to pathogenic expansion, oxidative stress, and inflammatory responses. Therefore, it is important to explore beneficial foods to prevent or suppress these abnormal responses. Successful application of probiotics in the functional foods has attracted increasing attention due to their immune regulatory, antioxidative, and antimicrobial properties. The aim of this review is to introduce immune regulatory antioxidative and antimicrobial effects of probiotics, which provides some basic theories for scientific research and development of potential functional foods.

3.
Peptides ; 121: 170131, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31408662

RESUMO

Extensive proliferation of vascular smooth muscle cell (VSMC) contributes to intimal hyperplasia following vascular injury, in which endoplasmic reticulum stress (ERS) plays a critical role. Intermedin (IMD) is a vascular paracrine/autocrine peptide exerting numerous beneficial effects in cardiovascular diseases. IMD overexpression could alleviate intimal hyperplasia. Here, we investigated whether endogenous IMD protects against intimal hyperplasia by inhibiting endoplasmic reticulum stress. The mouse left common carotid-artery ligation-injury model was established to induce intimal hyperplasia using IMD-/-mice and C57BL/6 J wild-type (WT) mice. Platelet-derived growth factor-BB (PDGF-BB) was used to stimulate the proliferation of VSMC. IMD-/- mice displayed exacerbated intimal hyperplasia induced by complete ligation of the left carotid artery at 14 d and 28 d compared to WT mice. However, IMD-deficiency had no effect on blood pressure, plasma triglyceride, and fasting blood glucose levels in mice. Furthermore, VSMCs derived from IMD-/- mice showed increased cell proliferation and dramatically elevated levels of glucose regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), ATF6 mRNA under PDGF-BB treatment compared to WT mice-derived VSMCs. In addition, exogenous administration of IMD significantly attenuated PDGF-BB-induced cell proliferation and GRP78, phosphorylase-inositol requiring enzyme 1α, ATF4, and ATF6 protein levels. Thus, endogenous IMD may counteract ERS to exert protective role in response to vascular injury and IMD is expected to be a therapeutic target for the prevention and treatment of restenosis.

4.
J Clin Neurosci ; 68: 211-217, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31303397

RESUMO

This study aimed to determine the efficacy of mindfulness practice on emotional state and cognitive function of community-living elderly with mild cognitive impairment. A randomized controlled trial was conducted with the experimental group undergoing a Mindfulness Awareness Program (MAP) and an active control group undergoing a Health Education Program (HEP) over a nine month period. Sessions were conducted weekly for the first three months and monthly for the remaining six months. Self-reported questionnaires in English and Chinese were administered through face-to-face interviews to collect data at baseline, three months and nine months. Descriptive statistics and analysis of covariance (ANCOVA) were used to analyse data. Fifty-five elderly participants aged sixty and above, were randomized to MAP (N = 28) and HEP (N = 27) programs. Participants in both intervention arms experienced decreases in depressive and anxiety symptoms over the nine-month period. A significant improvement occurred in the HEP group in depression scores at three months and anxiety scores at both three and nine months. There were no statistically significant changes on cognitive function in both groups over the nine-month period. Both the MAP and HEP can benefit the emotional states of community-living elderly with mild cognitive impairment. Our study supports the usefulness of group-based HEP as a low cost intervention for promoting active aging and psychological health in a community setting.

5.
Nanotechnology ; 30(44): 445701, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31342928

RESUMO

In this study, molecular dynamics simulations were used to investigate the micro-scale effects of modification of nano-SiO2 with commonly used silane coupling agents (KH550, KH560, KH570, and KH792) on the cellulose/nano-SiO2 interface. The relative optimum silane coupling agent and grafting density for nano-SiO2 modification to improve the cellulose/nano-SiO2 interface were determined. The results showed that at the same grafting density, modification of nano-SiO2 with KH792 yielded the highest interfacial binding energy and binding energy density, the largest number of hydrogen bonds at the cellulose/nano-SiO2 interface, the strongest binding to the cellulose chains, and the largest overlapping area at the cellulose/nano-SiO2 interface. We found that the non-bonding interaction energy played a decisive role in the energy of the model system and the interfacial interaction force mainly consisted of van der Waals forces and the hydrogen-bonding energy. When silane coupling agents with amino groups (KH550 and KH792) were used to modify nano-SiO2, the number of hydrogen bonds at the cellulose/nano-SiO2 interface was larger than that for unmodified nano-SiO2. When silane coupling agents without amino groups (KH560 and KH570) were used to modify nano-SiO2, the number of hydrogen bonds at the cellulose/nano-SiO2 interface was lower than the case for unmodified nano-SiO2. Nano-SiO2 modification with various amounts of KH792 was investigated. The results showed that the interfacial bonding energy increased with grafting density. When the grafting density was 1.57 nm-2, the interfacial bonding energy and number of hydrogen bonds formed at the cellulose/nano-SiO2 interface was relatively stable, which indicates that the interface had reached a relatively stable state. Modification of nano-SiO2 with KH792 achieved the greatest improvement of the cellulose/nano-SiO2 interface; this interface reached a relatively stable state when the grafting density of KH792 was 1.57 nm-2.

6.
J Agric Food Chem ; 67(30): 8348-8360, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31304751

RESUMO

We have recently demonstrated that tau hyperphosphorylation causes diabetic synaptic neurodegeneration of retinal ganglion cells (RGCs), which might be the earliest affair during the pathogenesis of diabetic retinopathy (DR). Thus, there is a pressing need to seek therapeutic agents possessing neuroprotective effects against tau hyperphosphorylation in RGCs for arresting the progression of DR. Here, using a well-characterized diabetes model of db/db mouse, we discovered that topical ocular application of 10 mg/kg/day of ginsenoside Rg1 (GRg1), one of the major active ingredients extracted from Panax ginseng and Panax notoginseng, ameliorated hyperphosphorylated tau-triggered RGCs synaptic neurodegeneration in diabetic mice. The neuroprotective effects of GRg1 on diabetic retinae were abrogated when retinal IRS-1 or Akt was suppressed by intravitreal injection with si-IRS-1 or topically coadministered with a specific inhibitor of Akt, respectively. However, selective repression of retinal GSK3ß by intravitreal administration of si-GSK3ß rescued the neuroprotective properties of GRg1 when Akt was inactivated. Therefore, the present study showed for the first time that GRg1 can prevent hyperphosphorylated tau-induced synaptic neurodegeneration of RGCs via activation of IRS-1/Akt/GSK3ß signaling in the early phase of DR. Moreover, our data clarify the potential therapeutic significance of GRg1 for neuroprotective intervention strategies of DR.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Ginsenosídeos/administração & dosagem , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas Substratos do Receptor de Insulina/metabolismo , Fármacos Neuroprotetores/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Ganglionares da Retina/efeitos dos fármacos , Proteínas tau/metabolismo , Animais , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Degeneração Neural/tratamento farmacológico , Degeneração Neural/genética , Degeneração Neural/metabolismo , Panax notoginseng/química , Fosforilação , Extratos Vegetais/administração & dosagem , Proteínas Proto-Oncogênicas c-akt/genética , Retina/patologia , Células Ganglionares da Retina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas tau/genética
7.
Nano Lett ; 19(8): 5577-5586, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31291113

RESUMO

Na-ion batteries are viewed as the alternative to Li-ion batteries for similar electrochemical properties, while they always suffer from a low capacity. Na-O2 batteries are important due to their high energy density; however, they are usually limited by high overpotential. In this manuscript, 16 different heterostructures of TMDs with MXenes (bare and O-terminated case) are constructed and their potential in the application of sodium-ion batteries (SIBs) and Na-O2 batteries is explored. Among these structures, it is proved that only the heterostructures of VS2 with O-terminated MXenes could load five layers of Na+ ions, while the others will have a distortion when Na+ ions intercalate or diffuse in the interlayer or the second adsorption layer. The ultrasmall diffusion barrier of Na+ ion denotes that these structures have a fast charge/discharge speed, and the ultrasmall open circuit voltages (OCVs) of 0.18 and 0.21 V prove that they are promising candidates for SIBs. The ultralow overpotential 0.55 V/0.20 V for the ηORR/ηOER means that the O facet of the VS2/Ti2CO2 heterostructure also has a great potential in the application of Na-O2 batteries. These simulations prove that the heterostructures constructed by TMDs with MXenes have great potential in SIBs and Na-O2 batteries and are important for future battery design.

8.
Appl Opt ; 58(16): 4414-4419, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251251

RESUMO

A terahertz metamaterial resonator consisting of two rectangular strips embedded in a closed-ring resonator is designed and investigated in this paper that can simultaneously generate the classical electromagnetically induced transparency effect and two Fano resonance modes. The formation of the transparent window and the Fano dips can be attributed to the coupling of the localized resonance modes between the closed-ring resonator and the two embedded rectangular strips. The effect of embedded rectangular strip sizes on the transmitted performance is discussed, and it is found that the resonant performance of the transparent window and Fano effect depends mainly on the length of the rectangular strips in the longitudinal direction. Based on this, two different device applications related to the embedded rectangular strips are discussed. The metamaterial proposed here could open up new avenues toward the control of terahertz waves in many technology-related areas.

9.
Sheng Li Xue Bao ; 71(3): 388-394, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31218329

RESUMO

The aim of this study was to determine the effects of extremely low frequency electromagnetic field (ELF-EMF) on energy metabolism and oxidative stress in Caenorhabditis elegans (C. elegans). Worms in three adult stages (young adult stage, egg-laying stage and peak egg-laying stage) were investigated under 50 Hz, 3 mT ELF-EMF exposure. ATP levels, ATP synthase activity in vivo, reactive oxygen species (ROS) content, and changes of total antioxidant capacity (TAC) were detected, and worms' oxidative stress responses were also evaluated under ELF-EMF exposure. The results showed that ATP levels were significantly increased under this ELF-EMF exposure, and mitochondrial ATP synthase activity was upregulated simultaneously. In young adult stage, worms' ROS level was significantly elevated, together with upregulated TAC but with a decreased ROS-TAC score indicated by principal component analysis. ROS level and TAC of worms had no significant changes in egg-laying and peak egg-laying stages. Based on these results, we concluded that ELF-EMF can enhance worm energy metabolism and elicit oxidative stress, mainly manifesting as ATP and ROS level elevation together with ATP synthase upregulation and ROS-TAC score decrease in young adult C. elegans.


Assuntos
Caenorhabditis elegans/efeitos da radiação , Radiação Eletromagnética , Metabolismo Energético , Estresse Oxidativo , Trifosfato de Adenosina/metabolismo , Animais , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Espécies Reativas de Oxigênio/análise
10.
Int J Rheum Dis ; 22(8): 1544-1552, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31240863

RESUMO

AIM: To examine the changes in the risks of death and cardiovascular diseases (CVD) in rheumatoid arthritis (RA) patients treated with conventional synthetic or biologic disease-modifying antirheumatic drugs (csDMARD or bDMARD) during 1997-2013. METHODS: Two cohorts of RA patients and their matched controls were identified from the National Health Insurance Research database. There were 1569 patients in the csDMARD cohort who received cyclosporine ≥50 mg/d with concomitant usage of ≥2 csDMARDs during 1997-2003. There were 1530 patients in the bDMARD cohort if patients had ≥1 claim for bDMARD during 2003-2011. Adjusted hazard ratios (aHRs) for the risk of death, myocardial infarction, and stroke, were assessed using the Kaplan-Meier survival curves and the Cox proportional hazards models. RESULTS: Compared with matched cohorts, the incidence of death was higher with csDMARD with a more than 6-fold increase (csDMARD vs controls: 33% vs 5%); while it only increased with a much smaller magnitude with bDMARD (bDMARD vs controls: 15% vs 11%). In addition, an increase in the reduction of incidence rate of stroke with bDMARD (bDMARD vs controls: 2% vs 5%) than that with csDMARD (csDMARD vs controls: 3% vs 4%) was found. Results from multivariate analysis showed that RA patients receiving bDMARD had a significantly lower increase in the risk of deaths (aHR 1.05; 95% CI 0.84-1.33) compared with those receiving csDMARD (aHR 8.75; 95% CI 7.43-10.31). In addition, bDMARD was associated with a higher reduction in the risk of stroke compared with csDMARD (bDMARD: aHR 0.37; 95% CI 0.22-0.62; csDMARD: aHR 0.73; 95% CI 0.51-1.05). CONCLUSION: Biologics used in RA patients have been shown to have a beneficial impact on improving clinical outcomes, including decreased risks of death and stroke. The economic burden from costs of biologics may be alleviated by improving outcomes.

11.
Asian Pac J Cancer Prev ; 20(5): 1377-1387, 2019 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-31127896

RESUMO

Objective: Three vaccines are available to Taiwanese young girls for cervical cancer (CC) prevention. Here we evaluate the cost-effectiveness of the two-dose (2D) AS04-adjuvanted HPV-16/18 vaccine (2D-AS04-HPV- 16/18v)+screening compared with a screening programme alone, with 2D human papillomavirus 6/11/16/18 vaccine (2D-4vHPVv)+screening, and with 2D/three-dose (3D) human papillomavirus 6/11/16/18/31/33/45/52/58 vaccine (9vHPVv)+screening, for Taiwan universal mass vaccination. Methods: A static Markov cohort model simulated the natural history of human papillomavirus (HPV) infection and CC screening for a 12-year-old cohort of Taiwanese girls (N=120,000). The model ran in 1-year cycles over the cohort's lifetime. Vaccine efficacy irrespective of HPV type was considered in the analysis for each vaccine. Input data were obtained from published literature, local databases, government reports and websites, and expert opinion. The analysis incorporated direct medical costs only, with an annual discount rate of 3.0%. The threshold was determined as 1 Gross Domestic Product per capita (New Taiwan dollar [NT$] 727,818; year 2016). Results: The 2D-AS04-HPV-16/18v+screening yielded 0.0365 quality-adjusted life year (QALY) gained at an additional cost of NT$ 5,770 per person compared with the screening programme alone. This resulted in an incremental cost-effectiveness ratio well below the threshold. Compared with 2D-4vHPVv+screening and 2D/3D-9vHPVv+screening, discounted results demonstrated additional QALYs gained at lower cost for 2D-AS04-HPV- 16/18v+screening, making it dominant over both 2D-4vHPVv+screening and 2D/3D-9vHPVv+screening. Conclusions: Vaccinating Taiwanese girls with 2D-AS04-HPV-16/18v in addition to screening to prevent CC is cost-effective compared with using a screening programme alone and the dominant option compared with 2D-4vHPVv+screening and 2D/3D-9vHPVv+screening.

12.
BMC Plant Biol ; 19(1): 190, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068146

RESUMO

BACKGROUND: The functional characteristics of SLAC/SLAH family members isolated from Arabidopsis thaliana, poplar, barley and rice have been comprehensively investigated. However, there are no reports regarding SLAC/SLAH family genes from Rosaceae plants. RESULTS: In this study, the function of PbrSLAH3, which is predominately expressed in pear (Pyrus bretschneideri) root, was investigated. PbrSLAH3 can rescue the ammonium toxicity phenomenon of slah3 mutant plants under high-ammonium/low-nitrate conditions. In addition, yeast two-hybrid and bimolecular fluorescence complementation assays confirmed that PbrSLAH3 interacts with PbrCPK32. Moreover, when PbrSLAH3 was co-expressed with either the Arabidopsis calcium-dependent protein kinase (CPK) 21 or PbrCPK32 in Xenopus oocytes, yellow fluorescence was emitted from the oocytes and typical anion currents were recorded in the presence of extracellular NO3-. However, when PbrSLAH3 alone was injected, no yellow fluorescence or anion currents were recorded, suggesting that anion channel PbrSLAH3 activity was controlled through phosphorylation. Finally, electrophysiological and transgene results showed that PbrSLAH3 was more permeable to NO3- than Cl-. CONCLUSION: We suggest that PbrSLAH3 crossing-talk with PbrCPK32 probably participate in transporting of nitrate nutrition in pear root.


Assuntos
Canais Iônicos/metabolismo , Nitratos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Quinases/metabolismo , Pyrus/enzimologia , Compostos de Amônio/toxicidade , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Fenômenos Eletrofisiológicos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Mutação/genética , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Pyrus/efeitos dos fármacos , Pyrus/genética , Xenopus
13.
Clin Chim Acta ; 495: 538-544, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31145896

RESUMO

CXC chemokine ligand 12 (CXCL12) is a specific chemokine ligand and plays a significant role in cell chemotaxis. Upon binding to CXC chemokine receptor 4 (CXCR4) or CXCR7, CXCL12 can activate different signaling cascades to regulate cell proliferation, migration, and metabolism. CXCL12 exerts a pro-atherogenic action by aggravating multiple pathogenesis of atherogenesis, including dyslipidemia, inflammation, neointima hyperplasia, angiogenesis, and insulin resistance. Serum CXCL12 levels are also markedly increased in patients with atherosclerosis-associated disease. The present review focuses on recent advances in CXCL12 research in the pathogenesis of atherosclerosis together with its clinical values. This may provide insight into potential novel therapies for atherosclerosis.

14.
J Phys Condens Matter ; 31(36): 365002, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31100737

RESUMO

Based on first principles calculations, we study the electronic properties of heterostructures formed by a 2D ferromagnetic insulator semihydrogenated graphene (SG) and topological insulator Bi2Se3 thin films of a few quintuple layers (QLs). It is found that the unsaturated C atoms in SG form bonds with Se atoms in Bi2Se3 thin film and the top surface states (at the interface) are strongly hybridized with SG. Due to breaking of time-reversal symmetry, the surface states open gaps of 40 meV and 150 meV for SG/3QL-Bi2Se3 and SG/5QL-Bi2Se3 heterostructures, respectively. Furthermore, a giant Rashba spin splitting is found induced by the SG layer.

15.
Food Funct ; 10(5): 2290-2312, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31032827

RESUMO

In recent years, natural polysaccharides have received increasing attention and become one type of popular dietary nutrient because of their various biological functions. In this paper, the sources, extraction, purification and structural characterization methods of natural polysaccharides are introduced. Natural polysaccharides are favorable for the proliferation of short chain fatty acid (SCFA)-producing bacteria, the presence of which can improve the intestinal microenvironment. Natural polysaccharides can not only enhance immunity, but also suppress excessive immune responses caused by various stimuli. In particular, natural polysaccharides can regulate immunity by acting directly on the immune cells and targeting the gut microbiota. Natural polysaccharides can enhance immunity by promoting beneficial microorganisms and strengthening the function of immune cells. However, natural polysaccharides can also suppress excessive inflammatory responses by improving the intestinal microbiota composition, strengthening intestinal barrier function, enhancing antioxidant activities, promoting SCFA production and reducing pro-inflammatory mediators. Therefore, a comprehensive review is presented on the impacts of natural polysaccharides on the gut microbiota and immune responses, as well as their interactions.

16.
Cell Death Dis ; 10(5): 335, 2019 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-31000722

RESUMO

The treatment of hyperprolactinemia is based on the use of dopamine agonists, mainly bromocriptine (BRC) and cabergoline (CAB). They reduce tumour size effectively and restore gonadal function. However, there is a difference in drug sensitivity between CAB and BRC in patients with prolactinoma, although the underlying mechanisms are still unknown. Thus, we investigated whether there are differences in tumour sensitivity to CAB and BRC and their possible differential mechanisms in two prolactinoma cell lines. In our study, we found that GH3 cells are more sensitive to BRC and that MMQ cells are more sensitive to CAB. Moreover, BRC and CAB elicited cell death via different pathways; BRC induced prolactinoma cell death mainly through the apoptosis pathway, and CAB induced pituitary prolactinoma cell death mainly via the autophagic cell death pathway. Using gene microarray analysis, we found that BRC induces the apoptosis of prolactinoma cells through the ERK/EGR1 signalling pathway, whereas CAB induces autophagic death by inhibiting the AKT/mTOR signalling pathway. Our study showed the difference in tumour sensitivity and differential mechanisms in BRC- and CAB-treated prolactinoma cells, which provides a theoretical basis for the accurate treatment of prolactinoma.

17.
J Cell Biochem ; 2019 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-30945338

RESUMO

Circular RNAs (circRNAs) are a novel class of endogenous noncoding RNAs that form covalently closed continuous loops without 3' end poly (A) tails and 5' end caps. circRNAs are more conservative and stable than linear RNA. circRNAs can specifically bind to microRNAs as competing endogenous RNA, thereby directly or indirectly regulating the expression of related genes. circRNAs have been implicated in several cancers including gastrointestinal (GI) cancers. Some circRNAs have the potential to become biological biomarkers and therapeutic targets of GI cancers. However, the multiple functional roles of circRNAs in GI cancers remain largely unclear.

18.
Cell Death Dis ; 10(4): 316, 2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30962417

RESUMO

Depression is a condition with a complex etiological pattern, whose effective treatments are highly limited. MicroRNAs (miRNAs) have been investigated in intensive studies owing to their involvement in pathophysiology of mood disorders. The current study aimed to elucidate the role of miR-301b in hippocampus in mouse models of depressive-like behavior. Microarray-based prediction identified the differentially expressed gene neuronal pentraxin II (NPTX2) related to mental depression. Next, the putative miR-301b binding sites on the 3'UTR of NPTX2 were verified. Then the effect of miR-301b on cognitive function of mice with depressive-like behavior was analyzed using the Morris water maze test. In addition, the regulation of miR-301b to NPTX2 and activation of NF-κB signaling pathway was assessed. Following that, the microglia activation and inflammation in hippocampus were evaluated, with the expressions of inflammatory factors being examined. At last, microglia were flow cytometrically sorted and the inflammatory reaction was also assessed in vitro. The obtained findings revealed that miR-301b targeted and negatively regulated NPTX2. Moreover, overexpressed miR-301b activated the NF-κB signaling pathway, as reflected by increasing protein expressions of p-NF-κB. Upregulated miR-301b accelerated cognitive impairment in mice with depressive-like behavior. In addition, overexpression of miR-301b activated microglia and stimulated inflammation in hippocampus, accompanied by enhanced release of tumor necrosis factor-α (TNF-α), interleukin-Iß (IL-Iß) and cyclooxygenase-2(COX-2). Taken together, the evidence provided by the current study indicated that overexpression of miR-301b augmented hippocampal microglia activation, thus exacerbating cognitive impairment and inflammation in mice with depressive-like behavior by activating the NF-κB signaling pathway.

19.
Leukemia ; 2019 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-30940905

RESUMO

Bone marrow (BM) niche responds to chemotherapy-induced cytokines secreted from acute lymphoblastic leukemia (ALL) cells and protects the residual cells from chemotherapeutics in vivo. However, the underlying molecular mechanisms for the induction of cytokines by chemotherapy remain unknown. Here, we found that chemotherapeutic drugs (e.g., Ara-C, DNR, 6-MP) induced the expression of niche-protecting cytokines (GDF15, CCL3 and CCL4) in both ALL cell lines and primary cells in vitro. The ATM and NF-κB pathways were activated after chemotherapy treatment, and the pharmacological or genetic inhibition of these pathways significantly reversed the cytokine upregulation. Besides, chemotherapy-induced NF-κB activation was dependent on ATM-TRAF6 signaling, and NF-κB transcription factor p65 directly regulated the cytokines expression. Furthermore, we found that both pharmacological and genetic perturbation of ATM and p65 significantly decreased the residual ALL cells after Ara-C treatment in ALL xenograft mouse models. Together, these results demonstrated that ATM-dependent NF-κB activation mediated the cytokines induction by chemotherapy and ALL resistance to chemotherapeutics. Inhibition of ATM-dependent NF-κB pathway can sensitize ALL to chemotherapeutics, providing a new strategy to eradicate residual chemo-resistant ALL cells.

20.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 33(4): 416-422, 2019 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-30983187

RESUMO

Objective: To compare the effectiveness of posterior lumbar interbody fusion (PLIF) by unilateral fenestration and bilateral decompression with ultrasounic osteotome and traditional tool total laminectomy decompression PLIF in the treatment of degenerative lumbar spinal stenosis. Methods: The clinical data of 48 patients with single-stage degenerative lumbar spinal stenosis between January 2017 and June 2017 were retrospectively analyzed. Among them, 27 patients were treated with unilateral fenestration and bilateral decompression PLIF with ultrasonic osteotome (group A), and 21 patients were treated with total laminectomy and decompression PLIF with traditional tools (group B). There was no significant difference in gender, age, stenosis segment, degree of spinal canal stenosis, and disease duration between the two groups ( P>0.05), which was comparable. The time of laminectomy decompression, intraoperative blood loss, postoperative drainage volume, and the occurrence of operation-related complications were recorded and compared between the two groups. Bridwell bone graft fusion standard was applied to evaluate bone graft fusion at last follow-up. Visual analogue scale (VAS) score was used to evaluate the patients' lumbar and back pain at 3 days, 3 months, and 6 months after operation. Oswestry disability index (ODI) score was used to evaluate the patients' lumbar and back function improvement before operation and at 6 months after operation. Results: The time of laminectomy decompression in group A was significantly longer than that in group B, and the intraoperative blood loss and postoperative drainage volume were significantly less than those in group B ( P<0.05). There was no nerve root injury, dural tear, cerebrospinal fluid leakage, and hematoma formation during and after operation in the two groups. All patients were followed up after operation, the follow-up time in group A was 6-18 months (mean, 10.5 months) and in group B was 6-20 months (mean, 9.3 months). There was no complication such as internal fixation fracture, loosening and nail pulling occurred during the follow-up period of the two groups. There was no significant difference in VAS scores between the two groups at 3 days after operation ( t=1.448, P=0.154); the VAS score of group A was significantly lower than that of group B at 3 and 6 months after operation ( P<0.05). The ODI scores of the two groups were significantly improved at 6 months after operation ( P<0.05), and there was no significant difference in ODI scores between the two groups before operation and at 6 months after operation ( P>0.05). At last follow-up, according to Bridwell criteria, there was no significant difference in bone graft fusion between the two groups ( Z=-0.065, P=0.949); the fusion rates of groups A and B were 96.3% (26/27) and 95.2% (20/21) respectively, with no significant difference ( χ 2=0.001, P=0.979 ). Conclusion: The treatment of lumbar spinal stenosis with unilateral fenestration and bilateral decompression PLIF with ultrasonic osteotome can achieve similar effectiveness as traditional tool total laminectomy and decompression PLIF, reduce intraoperative blood loss and postoperative drainage, and reduce lumbar back pain during short-term follow-up. It is a safe and effective operation method.


Assuntos
Fusão Vertebral , Estenose Espinal , Ultrassom , Humanos , Vértebras Lombares , Estudos Retrospectivos , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Resultado do Tratamento
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