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1.
Polymers (Basel) ; 15(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37447524

RESUMO

In this study, the thermoset-thermoplastic structure was produced through a co-curing technique together with an injection overmolding technique. Continuous fiber reinforced thermoset composite (TSC) was selected as thermoset material, while polyamide 6 (PA 6) was chosen as thermoplastic material. The influence of injection temperature, preheating temperature and injection speed on the interfacial bonding strength of hybrid thermoset-thermoplastic composites was investigated. The results show that increasing injection temperature and preheating temperature have significant effects on the increase in bonding strength, while injection speed has little effect on it. In addition, the bonding strength of the co-cured interface is enhanced after the injection overmolding process, which is further studied through molecular dynamic (MD) simulation. The molecular dynamic simulation result shows that the high temperature and pressure during the injection process only have a weak effect on enhancing the bonding strength of the co-cured interface, while the chemical reaction at the co-cured interface is the main reason for the enhancement. Furthermore, the more chemical reactions occur at the interface, the stronger the interface will be.

2.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447814

RESUMO

The prediction of soil properties at different depths is an important research topic for promoting the conservation of black soils and the development of precision agriculture. Mid-infrared spectroscopy (MIR, 2500-25000 nm) has shown great potential in predicting soil properties. This study aimed to explore the ability of MIR to predict soil organic matter (OM) and total nitrogen (TN) at five different depths with the calibration from the whole depth (0-100 cm) or the shallow layers (0-40 cm) and compare its performance with visible and near-infrared spectroscopy (vis-NIR, 350-2500 nm). A total of 90 soil samples containing 450 subsamples (0-10 cm, 10-20 cm, 20-40 cm, 40-70 cm, and 70-100 cm depths) and their corresponding MIR and vis-NIR spectra were collected from a field of black soil in Northeast China. Multivariate adaptive regression splines (MARS) were used to build prediction models. The results showed that prediction models based on MIR (OM: RMSEp = 1.07-3.82 g/kg, RPD = 1.10-5.80; TN: RMSEp = 0.11-0.15 g/kg, RPD = 1.70-4.39) outperformed those based on vis-NIR (OM: RMSEp = 1.75-8.95 g/kg, RPD = 0.50-3.61; TN: RMSEp = 0.12-0.27 g/kg; RPD = 1.00-3.11) because of the higher number of characteristic bands. Prediction models based on the whole depth calibration (OM: RMSEp = 1.09-2.97 g/kg, RPD = 2.13-5.80; TN: RMSEp = 0.08-0.19 g/kg, RPD = 1.86-4.39) outperformed those based on the shallow layers (OM: RMSEp = 1.07-8.95 g/kg, RPD = 0.50-3.93; TN: RMSEp = 0.11-0.27 g/kg, RPD = 1.00-2.24) because the soil sample data of the whole depth had a larger and more representative sample size and a wider distribution. However, prediction models based on the whole depth calibration might provide lower accuracy in some shallow layers. Accordingly, it is suggested that the methods pertaining to soil property prediction based on the spectral library should be considered in future studies for an optimal approach to predicting soil properties at specific depths. This study verified the superiority of MIR for soil property prediction at specific depths and confirmed the advantage of modeling with the whole depth calibration, pointing out a possible optimal approach and providing a reference for predicting soil properties at specific depths.


Assuntos
Agricultura , Solo , Espectrofotometria Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho , Nitrogênio/análise , Solo/química , Espectrofotometria Infravermelho/normas , Espectroscopia de Luz Próxima ao Infravermelho/normas , Modelos Teóricos , Agricultura/instrumentação , Agricultura/métodos
3.
J Colloid Interface Sci ; 648: 768-777, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321096

RESUMO

Although sodium-ion hybrid supercapacitor (Na-ion HSC) has attracted great interest, exploitation of suitable cathode materials for reversible Na+ insertion reaction remains a challenge. Herein, a novel binder-free composite cathode with highly crystallized NiFe Prussian blue analogue (NiFePBA) nanocubes in-situ grown on reduced graphene oxide (rGO) was fabricated via sodium pyrophosphate (Na4P2O7)-assisted co-precipitation and the subsequent ultrasonic spraying and chemical reduction. Profiting from the low-defect PBA framework and close interface contact of PBA and conductive rGO, the NiFePBA/rGO/carbon cloth composite electrode exhibits a high specific capacitance of 451F g-1, remarkable rate performance and satisfactory cycling stability in aqueous Na2SO4 electrolyte. Impressively, the aqueous Na-ion HSC assembled with the composite cathode and activated carbon (AC) anode manifests a high energy density of 51.11 Wh kg-1, superb power density of 10 kW kg-1 and the intriguing cycling stability. This work may open a door for scalable fabrication of binder-free PBA cathode material for aqueous Na-ion storage.

4.
J Orthop Surg Res ; 18(1): 300, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055802

RESUMO

BACKGROUND: Joint contracture causes a decrease in range of motion (ROM), which severely affects activities of daily living of patients. We have investigated the effectiveness of a multidisciplinary rehabilitation on joint contracture by rat model. METHODS: We used 60 Wistar rats in this study. The rats were divided into five groups as follows: group 1 was the normal control group; except the group 1, we created left hind limb knee joint contracture using Nagai method for other four groups. The joint contracture modeling group 2 was the model control group for monitoring the spontaneous recovery, and other three groups were given different rehabilitation treatments; for example, group 3 was treadmill running group; group 4 was medication group; group 5 was treadmill running plus medication group. The left hind limbs knee joint ROM and the femoral blood flow indicators (FBFI) including PS, ED, RI, and PI were measured right before and after the 4 weeks of rehabilitation. RESULT: After 4 weeks of rehabilitation treatments, the measured values of ROM and FBFI are compared with the corresponding values of group 2. Firstly, we did not see clear difference in the values of ROM and FBFI for group 2 before and after 4 weeks spontaneous recovery. The improvement of left lower limb ROM for group 4 and group 5 as compared to the group 2 was statistically significant (p < 0.05), whereas a less recovery for group 3 was observed. However as compared to the group 1, we did not observe full recovery in ROM of group 4 and group 5 after 4 weeks of rehabilitation. The PS and ED level for rehabilitation treatment groups was significantly higher than those modeling ones (Tables 2, 3,  Figs. 4, 5), while the RI and PI values show the contrary trends (Tables 4, 5, Figs. 6, 7). CONCLUSION: Our results indicate that multidisciplinary rehabilitation treatments had a curative effect on both contracture of joints and the abnormal femoral circulations.


Assuntos
Atividades Cotidianas , Contratura , Humanos , Ratos , Animais , Ratos Wistar , Articulação do Joelho , Modelos Animais de Doenças , Hemodinâmica , Amplitude de Movimento Articular
5.
J Colloid Interface Sci ; 626: 59-67, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35780552

RESUMO

Despite of great interests in aqueous asymmetric supercapacitors (ASC), their performance is often restricted by unsatisfactory specific capacitance of anode materials. Herein, accordion-like V2CTx MXene has been prepared and exploited as novel anode material for aqueous ASC in neutral ZnSO4 electrolyte. Profitting from the layered structure with expanded interlayer distance, the V2CTx electrode exhibits a high specific capacitance of 481F g-1 at 1 A g-1, a reasonable rate performance and intriguing cycling stability with capacitance retention of 84.3% after 60,000 cycles at 10 A g-1 in 2 M ZnSO4 electrolyte. Furthermore, an ASC device based on the V2CTx as anode and activated carbon (AC) as cathode was successfully assembled in the ZnSO4 electrolyte, which achieves a wide potential window up to 1.8 V. Remarkably, the V2CTx//AC ASC delivers a high energy density of 34 W h kg-1 at a power density of 954 W kg-1, as well as superb cycling stability with capacitance retention of 79% even after 100,000 charge/discharge cycles at 10 A g-1. The intriguing electrochemical performance, especially the ultralong cycling life, make the V2CTx MXene electrode promising in aqueous energy storage devices.

6.
Dalton Trans ; 51(11): 4491-4501, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35230381

RESUMO

The rational design of composite electrodes that may take full advantage of pseudocapacitive metal oxides and graphene is still challenging. Herein, nickel cobaltate (NiCo2O4) nanoparticle-anchored crumpled graphene microspheres (CGMs) were fabricated through a simple spray-assisted self-assembly process and used as a composite electrode for aqueous supercapacitors. Due to the porous spherical architecture and well-dispersed NiCo2O4 nanoparticles on graphene, the NiCo2O4/CGM electrode displays ideal electrochemical performance, including a specific capacitance of 369.8 F g-1 (at 1 A g-1), good rate performance of 85% capacitance retention even at 10 A g-1 and intriguing cycling stability. An aqueous asymmetric supercapacitor (ASC) with an operating voltage of 1.6 V was then assembled using the NiCo2O4/CGM composite and nitrogen-doped CGM (N-CGM) as the positive and negative electrodes in KOH electrolyte, respectively. The ASC device exhibited an excellent energy density of 24.7 W h kg-1 at a power density of 799.6 W kg-1, and an ultralong cycling life with a capacitance retention of 85% after 50 000 cycles. The satisfactory electrochemical performance and ultralong cycling stability indicate that the NiCo2O4/CGM electrode has promising applications in advanced supercapacitors.

7.
Immunology ; 164(4): 792-802, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34379797

RESUMO

Adaptive immunity and innate immunity have been implicated in the pathogenesis of abdominal aortic aneurysm (AAA), and damage and remodelling in the tunica media are a focus of the aneurysm development. Thus, identification of key immune cells or molecules that might be targets for the treatment of AAA is critical. We characterized the innate immune cells in human AAA tissue specimens by flow cytometry and found that apart from other lymphocytes, many invariant natural killer T (iNKT) cells marked as CD3 and Va24Ja18 had invaded the aortic tissues and were numerous, especially in the tunica media. These infiltrating iNKT cells have a high expression of CD69, indicating a highly active function. We were interested in whether iNKT cells could be the drivers of media damage in AAA. To answer this question, we used an AAA mouse model induced by angiotensin II (Ang II) infusion, which can reproduce the inflammatory response of AAA in mouse, which was confirmed by RNAseq. The results showed that the incidence of AAA was significantly higher after administration of α-galactosylceramide (α-GalCer), a synthetic glycolipid that activates iNKT cells via CD1d, compared with the Ang II-induced AAA alone (61·54% vs 31·82%) in mice. Histopathological and immunofluorescent staining results showed significantly more severe inflammatory infiltration and pathological lesions in the Ang II+α-GalCer treatment group. These results are highly suggestive that activated iNKT cells greatly contribute to AAA development and that the control of the activation state in iNKT cells may represent an important therapeutic strategy for AAA.


Assuntos
Aneurisma da Aorta Abdominal/etiologia , Aneurisma da Aorta Abdominal/metabolismo , Suscetibilidade a Doenças , Ativação Linfocitária/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Animais , Aneurisma da Aorta Abdominal/patologia , Biomarcadores , Modelos Animais de Doenças , Citometria de Fluxo , Humanos , Subpopulações de Linfócitos/metabolismo , Camundongos
8.
Sci Total Environ ; 789: 147778, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34051498

RESUMO

Controlled-release urea (CRU) fertilizer application has been shown to improve crop yield and nitrogen (N) use efficiency. However, its effects when mixed with conventional urea fertilizer on soil aggregate stability, humic acid (HA) molecular composition and crop N uptake remain unclear. Soil and plant samples were collected from a long-term (2008-2019) experiment on field maize (Zea mays L., 'Zhengdan 958') which included two types of fertilizers [conventional urea fertilizer (CUF), blended CUF with CRU fertilizer (CRF)], four N application rates (0, 150, 300 and 450 kg ha-1), each in three replicates. The results showed that at 300 kg N ha-1, compared to CUF treatment, the CRF treatment significantly improved soil aggregate characteristics [aggregate content with particle size larger than 0.25 mm (R0.25) by 9.6%, mean weight diameter by 19.8%, and geometric mean diameter by 21.7%]. CRF treatment also increased HA content by 5.5%, fulvic acid (FA) by 5.5%, lignin-like molecules by 0.94 times, and protein-like molecules by 3.69 times. At grain-filling stage, CRF treatments significantly increased the sum of soil NH4+-N and NO3--N content by 23.3-24.5%, sap bleeding rate by 12.8-18.2% and N delivery rate through bleeding sap by 60.6-87.7% compared to CUF treatments at the same N application rate. At the same rate of N application, the CRF treatments significantly improved the average yield during three growing seasons by 9.4-14.0% in contrast with CUF treatments. The regression equations showed that the maximum yield was 8294 kg ha-1 for CUF at the application rate of 312 kg N ha-1 while it was 9890 kg ha-1 for CRF at the application rate of 286 kg N ha-1. We conclude that the long-term application of CRF changed the HA molecular structure, enhanced the water stable aggregates, improved crop N uptake, and increased economically viable maize yield.


Assuntos
Fertilizantes , Solo , Agricultura , Preparações de Ação Retardada , Substâncias Húmicas , Nitrogênio , Ureia , Zea mays
9.
Carcinogenesis ; 42(4): 640-649, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33417668

RESUMO

Impairment of genome instability drives the development of cancer by disrupting anti-cancer barriers. Upon genotoxic insults, DNA damage responsive factors, notably ATM kinase, is crucial to protect genomic integrity while promoting cell death. Meanwhile, cytotoxic therapy-inducing DNA lesions is double-edged sword by causing cancer metastasis based on animal models and clinical observations. The underlying mechanisms for the procancer effect of cytotoxic therapies are poorly understood. Here, we report that cancer cells subjected to cytotoxic treatments elicit dramatic alteration of gene expression controlling the potential of epithelium-mesenchyme transition (EMT). Resultantly, EMT-dependent cell mobility is potently induced upon DNA damage. This stimulation of EMT is mainly Ataxia-Telangiectasia-mutated (ATM)-dependent, as the chemical inhibitor specifically inhibiting ATM kinase activity can suppress the EMT gene expression and thus cell mobility. At last, we show that cancer cells with ATM activation display increased metastatic potential in ovarian cancer tissues. Taken together, we reveal a novel role of ATM in promoting metastatic potential of cancer cells by favoring EMT gene expression.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias/genética , Movimento Celular/genética , Proliferação de Células/efeitos dos fármacos , Dano ao DNA/genética , Regulação Neoplásica da Expressão Gênica/genética , Instabilidade Genômica/genética , Humanos , Metástase Neoplásica , Neoplasias/patologia
10.
Cell Death Dis ; 11(9): 742, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917854

RESUMO

Chronic inflammation induced by persistent viruses infection plays an essential role in tumor progression, which influenced on the interaction between the tumor cells and the tumor microenvironment. Our earlier study showed that ATR, a key kinase participant in single-stranded DNA damage response (DDR), was obviously activated by Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC). However, how EBV-induced ATR activation promotes NPC by influencing inflammatory microenvironment, such as tumor-associated macrophages (TAMs), remains elusive. In this study, we showed that EBV could promote the expression of p-ATR and M2-type TAMs transformation in clinical NPC specimens. The expression of p-ATR and M2-type TAMs were closely correlated each other and involved in TNM stage, lymph node metastasis and poor prognosis of the patients. In addition, the expression levels of CD68+CD206+, Arg1, VEGF, and CCL22 were increased in EB+ CNE1 cells, and decreased when ATR was inhibited. In the nude mice, EBV-induced ATR activation promoted subcutaneous transplanted tumor growth, higher expression of Ki67 and lung metastasis via M2-type TAMs recruitment. Experimental data also showed that the polarization of M2, the declined tumor necrosis factor-α (TNF-α) and increased transforming growth factor-ß (TGF-ß) were associated with ATR. Meanwhile, ATR activation could promote PPAR-δ and inhibited c-Jun and p-JNK expression, then downregulate JNK pathway. Collectively, our current study demonstrated the EBV infection could activate the ATR pathway to accelerate the transition of TAMs to M2, suggesting ATR knockdown could be a potential effective treatment strategy for EBV-positive NPC.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Imunoterapia/métodos , Ativação de Macrófagos/genética , Carcinoma Nasofaríngeo/genética , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/patologia , Microambiente Tumoral
11.
Korean J Radiol ; 21(12): 1294-1304, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32783415

RESUMO

OBJECTIVE: To determine whether T1 mapping could monitor the dynamic changes of injury in myocardial infarction (MI) and be histologically validated. MATERIALS AND METHODS: In 22 pigs, MI was induced by ligating the left anterior descending artery and they underwent serial cardiovascular magnetic resonance examinations with modified Look-Locker inversion T1 mapping and extracellular volume (ECV) computation in acute (within 24 hours, n = 22), subacute (7 days, n = 13), and chronic (3 months, n = 7) phases of MI. Masson's trichrome staining was performed for histological ECV calculation. Myocardial native T1 and ECV were obtained by region of interest measurement in infarcted, peri-infarct, and remote myocardium. RESULTS: Native T1 and ECV in peri-infarct myocardium differed from remote myocardium in acute (1181 ± 62 ms vs. 1113 ± 64 ms, p = 0.002; 24 ± 4% vs. 19 ± 4%, p = 0.031) and subacute phases (1264 ± 41 ms vs. 1171 ± 56 ms, p < 0.001; 27 ± 4% vs. 22 ± 2%, p = 0.009) but not in chronic phase (1157 ± 57 ms vs. 1120 ± 54 ms, p = 0.934; 23 ± 2% vs. 20 ± 1%, p = 0.109). From acute to chronic MI, infarcted native T1 peaked in subacute phase (1275 ± 63 ms vs. 1637 ± 123 ms vs. 1471 ± 98 ms, p < 0.001), while ECV progressively increased with time (35 ± 7% vs. 46 ± 6% vs. 52 ± 4%, p < 0.001). Native T1 correlated well with histological findings (R² = 0.65 to 0.89, all p < 0.001) so did ECV (R² = 0.73 to 0.94, all p < 0.001). CONCLUSION: T1 mapping allows the quantitative assessment of injury in MI and the noninvasive monitoring of tissue injury evolution, which correlates well with histological findings.


Assuntos
Imagem Cinética por Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico por imagem , Doença Aguda , Animais , Doença Crônica , Meios de Contraste/química , Modelos Animais de Doenças , Processamento de Imagem Assistida por Computador , Masculino , Infarto do Miocárdio/patologia , Miocárdio/patologia , Reprodutibilidade dos Testes , Suínos
12.
Med Hypotheses ; 143: 109842, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32425304

RESUMO

The incidence of COVID-19 in children and teenagers is only about 2% in China. Children had mild symptoms and hardly infected other children or adults. It is worth considering that children are the most vulnerable to respiratory pathogens, but fatal SARS-like virus had not caused severe cases among them. According to the pathological studies of COVID-19 and SARS, a sharp decrease in T lymphocytes leads to the breakdown of the immune system. The cellular immune system of children differs from that of adults may be the keystone of atypical clinical manifestations or even covert infection. The frequent childhood vaccinations and repeated pathogens infections might be resulting in trained immunity of innate immune cells, immune fitness of adaptive immune cells or cross-protection of antibodies in the children. Therefore, due to lack of specific vaccine, some vaccines for tuberculosis, influenza and pneumonia may have certain application potential for the front-line health workers in the prevention and control of COVID-19. However, for high-risk susceptible populations, such as the elderly with basic diseases such as hypertension and diabetes, it is necessary to explore the remedial effect of the planned immune process on their immunity to achieve the trained immunity or immune fitness, so as to improve their own antiviral ability.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Vacinação , Adolescente , Anticorpos Antivirais/imunologia , Betacoronavirus , COVID-19 , Criança , Pré-Escolar , China/epidemiologia , Coinfecção , Humanos , Programas de Imunização , Lactente , SARS-CoV-2 , Linfócitos T/citologia
13.
Mol Med Rep ; 18(1): 564-570, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29749448

RESUMO

With the increase in applications of superparamagnetic iron oxide nanoparticles (SPIONs) in biomedicine, it is essential to investigate the bio­security of these nanoparticles, especially with respect to the human immune system. In the present study, the biological effects of dextran­coated superparamagnetic iron oxide nanoparticles (Dex­SPIONs) on human primary monocyte cells were evaluated. The results of the present study demonstrated that Dex­SPIONs can be identified in phagosomes or freed in the cytoplasm and did not affect cell viability or induce apoptosis. Notably, there were certain bulky vacuoles and a number of pseudopodia from the cell membrane, suggesting potential activation of human monocyte cells. In addition, the expression levels of pro­inflammatory cytokines interleukin (IL)­1ß and tumor necrosis factor (TNF)­α were also increased following treatment with Dex­SPIONs. Simultaneously, the phosphorylation levels of mitogen­activated protein kinase (MAPK) p38, c­Jun N­terminal kinase 1 and extracellular signal regulated kinase were markedly enhanced following nanoparticle exposure and MAPK inhibitors could abate the production of IL­1ß and TNF­α. The results of the present study demonstrated that Dex­SPIONs could activate human monocyte cells and that activation of MAPK pathway may be involved in these effects.


Assuntos
Dextranos/farmacologia , Interleucina-1beta/genética , Sistema de Sinalização das MAP Quinases , Nanopartículas de Magnetita/química , Monócitos/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Adulto , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Monócitos/metabolismo
14.
Biomarkers ; 22(1): 14-18, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27295539

RESUMO

CONTEXT: Sepsis is now the leading cause of death in the noncardiovascular intensive care unit (ICU). OBJECTIVE: To investigate whether polymorphisms in IL21 gene contribute to sepsis susceptibility. MATERIALS AND METHODS: Three single-nucleotide polymorphisms of IL21 (rs907715, rs2055979, rs12508721) were genotyped by TaqMan assay in patients with sepsis and control subjects. RESULTS: Polymorphisms rs2055979 and rs12508721 in IL21 were more frequent in sepsis patients compared to general population. But allele frequency of rs907715 was not significantly different between sepsis patients and control subjects. CONCLUSION: Polymorphisms in IL21 may be associated with sepsis risk.


Assuntos
Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Sepse/genética , Estudos de Casos e Controles , Frequência do Gene , Predisposição Genética para Doença , Humanos , Unidades de Terapia Intensiva , Risco
15.
Biomed Res Int ; 2015: 207684, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26161389

RESUMO

This study aims to investigate the regulative effects of microRNA-451a (miR-451a) on cell proliferation and sensitivity to tamoxifen in breast cancer cells. In cell culture experiments, the lentiviral vectors of pHBLV-miR-451a and pHBLV-miR-451a sponge were constructed and used to transfect MCF-7 and LCC2 cells. The transfection efficiency was tested by fluorescent observation, and cell lines with stable over- or downregulated expression of miR-451a were established. The expression of miR-451a and the target gene macrophage migration inhibitory factor (MIF) were detected by real-time reverse transcriptase polymerase chain reaction and/or western blot. Moreover, MTT assay, colony formation, and Transwell invasion assays were also performed. Data showed that the recombinant lentiviral vectors were constructed correctly, and the virus titer was 1 × 10(8) CFU/mL. The stable transfected cells were obtained. Overexpression of miR-451a downregulated MIF expression in mRNA and protein levels and inhibited cell proliferation, colony formation, and invasion of breast cancer cells. Downregulation of miR-451a upregulated MIF expression and increased breast cancer cell growth, invasion, and tamoxifen sensitivity. In summary, the miR-451a/MIF pathway may play important roles in the biological properties of breast cancer cells and may be a potential therapeutic target for breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , MicroRNAs/metabolismo , Tamoxifeno/uso terapêutico , Sequência de Bases , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Oxirredutases Intramoleculares/genética , Lentivirus/metabolismo , Fatores Inibidores da Migração de Macrófagos/genética , MicroRNAs/genética , Dados de Sequência Molecular , Invasividade Neoplásica , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de RNA , Tamoxifeno/farmacologia , Transdução Genética , Transfecção , Montagem de Vírus/efeitos dos fármacos
16.
Mol Med Rep ; 12(1): 20-30, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25739039

RESUMO

Umbilical cord mesenchymal stem cells (UC-MSCs) have been suggested as a candidate for various clinical applications, however, major limitations include the lack of organ-specific accumulation and low survival rates of transplanted cells. In the present study, it was hypothesized that the paracrine effects of UC­MSCs may enhance stem cell-based tissue repair and regeneration by promoting the specific homing of stem/progenitor cells and the overall ability to drive them to the damaged area. UC-MSCs-derived conditioned medium (UC-CM) was analyzed using liquid chip and ELISA techniques. In vitro tube formation assays of human umbilical vein endothelial cells (HUVECs) and UC-MSCs were then performed to assess the angiogenic properties of UC-CM. Subsequently, UC-MSCs, HUVECs and fibroblasts were labeled with PKH26 for an in vivo cell migration assay. The expression levels of C-X-C chemokine receptor 4 (CXCR4), C-C chemokine receptor 2 (CCR2) and c-met were determined in the UC-MSCs, HUVECs and fibroblasts using reverse transcription-quantitative polymerase chain reaction and flow cytometry. UC-CM was incubated with or without antibodies, and the contribution of stromal cell-derived factor 1 (SDF-1), monocyte chemotactic protein 1 (MCP-1) and hepatocyte growth factor (HGF) on the migration of cells was investigated in vitro. The results demonstrated that UC-MSCs secreted different cytokines and chemokines, including increased quantities of SDF-1, MCP-1 and HGF, in addition to the angiogenic factors, vascular cell adhesion protein-1, interleukin-8, insulin-like growth factor-1 and vascular endothelial growth factor. The total lengths of the tubes were significantly increased in the UC-MSCs and HUVECs incubated in UC-CM compared with those incubated in Dulbecco's modified Eagle's medium. In vivo cell migration assays demonstrated that UC-CM was a chemotactic stimulus for the UC-MSCs and HUVECs. In vitro Matrigel migration and scratch healing assays demonstrated that UC-CM increased the migration of CXCR4-positive or/and CCR2-positive cells in a dose-dependent manner. In addition, different molecules were screened under antibody-based blocking migration conditions. The data revealed that the SDF-1/CXCR4 and MCP-1/CCR2 axes were involved in the chemoattractive activity of UC-CM and suggested that the effective paracrine factor of UC-CM is a large complex rather than a single factor. The results of the present study supported the hypothesis that UC-MSCs release soluble factors, which may extend the therapeutic applicability of stem cells.


Assuntos
Movimento Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Células-Tronco Mesenquimais/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Quimiocina CCL2/metabolismo , Quimiocina CXCL12/metabolismo , Meios de Cultivo Condicionados/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Neovascularização Fisiológica/genética , Receptores CCR2/metabolismo , Receptores CXCR4/metabolismo , Cordão Umbilical/metabolismo
17.
Microbiol Immunol ; 59(3): 105-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25644086

RESUMO

Oral lichen planus (OLP) is a chronic inflammatory disorder of oral mucosa of unknown cause. Microbial infection and dysimmunity appear to play important roles in its pathogenesis. In this study, differences in genetic profiling of salivary microbial communities in two subtypes of OLP and healthy controls were evaluated by means of PCR-denaturing gradient gel electrophoresis (DGGE). Additionally, ELISA was used to investigate the possible role of Th17 in lesion formation by detecting two related cytokines IL-17 and IL-23 in the saliva of OLP patients. When the DGGE profiles were analyzed, the bacterial populations were found to be significantly less rich in subjects with reticular and erosive OLP than in healthy controls. There was significantly less microbial diversity, as denoted by the Shannon index, in saliva samples from subjects with erosive OLP than in those from healthy controls. Cluster analysis and principal component analysis showed that the DGGE profiles formed distinctly group-specific clusters. Salivary concentrations of IL-17 in subjects with erosive OLP group were significantly higher than in those with reticular OLP and healthy controls. What's more, significantly positive correlations were observed between salivary IL-17 concentrations and disease clinical scores. Microbial richness and diversity was negatively correlated with salivary IL-17 concentrations. These results suggest there is significantly less salivary bacterial diversity and complexity in subjects with OLP han in healthy controls and that the shifted community composition is closely related to an immune cytokine, IL-17.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Citocinas/imunologia , Líquen Plano Bucal/imunologia , Líquen Plano Bucal/microbiologia , Saliva/microbiologia , Células Th17/imunologia , Adulto , Bactérias/classificação , Bactérias/genética , Citocinas/genética , Feminino , Humanos , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-23/genética , Interleucina-23/imunologia , Líquen Plano Bucal/genética , Masculino , Pessoa de Meia-Idade , Filogenia , Saliva/imunologia , Adulto Jovem
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 30(8): 868-71, 2014 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-25108442

RESUMO

OBJECTIVE: To compare the efficiency of pamidronate (PAM) and isopentenyl pyrophosphate (IPP) to stimulate γδ T cell expansion from human peripheral blood and explore the optimized expansion conditions. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated by Ficoll-Paque gradient centrifugation, and then cultured in RPMI1640 medium supplemented with 10% fetal bovine serum, IPP (1.0, 5.0, 10.0, 15.0 µg/mL) or PAM (2.0, 5.0, 8.0, 12.0 µg/mL), and IL-2 (100.0, 200.0, 500.0 IU/mL). The cells were observed and collected. The number and proportion of CD3⁺TCRδ2⁺ γδ T cells stimulated by PAM or IPP in total lymphocytes were evaluated by flow cytometry and the expansion efficiency was calculated. RESULTS: After 14 days, the ratios of γδ T cells in total lymphocytes in IPP group and PAM group increased to 81.3% and 78.5%, respectively. This indicated that both IPP and PAM could effectively stimulate γδ T cell expansion and there was no significant difference in the efficiency of expansion between the two groups (P>0.05). CONCLUSION: PAM has the similar ability with IPP to stimulate γδ T cell expansion in vitro. PAM could become more economical and practical choice for stimulating γδ T cell expansion.


Assuntos
Difosfonatos/farmacologia , Hemiterpenos/farmacologia , Compostos Organofosforados/farmacologia , Fosfatos/farmacologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Subpopulações de Linfócitos T/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Citometria de Fluxo , Humanos , Interleucina-2/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Pamidronato , Subpopulações de Linfócitos T/metabolismo , Fatores de Tempo
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