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1.
Chemosphere ; 310: 136784, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36241104

RESUMO

With the wide application of nanomaterials (NMs) in agriculture, it is particularly important to assess the impact of these NMs on soil microorganisms. In this study, different varieties of soybean rhizosphere microorganisms (RM) were employed to simulate the alleviate effect of molybdenum nanoparticles (Mo NPs) induced stress in presence of soybean plants. Mo NPs caused serious toxic effects on soybean growth and nitrogen fixation at a concentration of 100 mg kg-1: plant height and biomass were reduced by 56.4% and 82.8%, respectively, and the ability to fix nitrogen was almostly lost. However, after adding different varieties of soybean RM (RM-Williams 82, RM-Youchun 1204, and RM-Zhongdou 41), the stress caused by high concentrations of Mo NPs on soybean plants was significantly reduced. The plant height, root length, biomass, and nitrogen fixation ability were improved by 70.8%, 80.7%, 145.8%, and 349.8%, respectively, following the addition of soybean RM-Williams 82. High-throughput sequencing revealed that Mo NPs treatment affected the microbial community structure. Among them, Flavisolibacter and Caulobacter genera abundance increased significantly, which might be the key factor in relieving Mo NPs-induced stress on soybean growth. These findings suggest a novel mode of RM as a promising strategy to prevent deleterious effects of stress with NPs on plants in the future.


Assuntos
Fabaceae , Microbiota , Nanoestruturas , Rizosfera , Solo/química , Glycine max , Microbiologia do Solo , Molibdênio/farmacologia , Nanoestruturas/toxicidade
2.
Front Aging Neurosci ; 14: 994130, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262887

RESUMO

Alzheimer's disease (AD) is a complex, and multifactorial neurodegenerative disease. Previous studies have revealed that oxidative stress, synaptic toxicity, autophagy, and neuroinflammation play crucial roles in the progress of AD, however, its pathogenesis is still unclear. Recent researches have indicated that ferroptosis, an iron-dependent programmed cell death, might be involved in the pathogenesis of AD. Therefore, we aim to screen correlative ferroptosis-related genes (FRGs) in the progress of AD to clarify insights into the diagnostic value. Interestingly, we identified eight FRGs were significantly differentially expressed in AD patients. 10,044 differentially expressed genes (DEGs) were finally identified by differential expression analysis. The following step was investigating the function of DEGs using gene set enrichment analysis (GSEA). Weight gene correlation analysis was performed to explore ten modules and 104 hub genes. Subsequently, based on machine learning algorithms, we constructed diagnostic classifiers to select characteristic genes. Through the multivariable logistic regression analysis, five features (RAF1, NFKBIA, MOV10L1, IQGAP1, FOXO1) were then validated, which composed a diagnostic model of AD. Thus, our findings not only developed genetic diagnostics strategy, but set a direction for further study of the disease pathogenesis and therapy targets.

3.
Oncol Lett ; 22(1): 565, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34113393

RESUMO

Glioma is the most common type of primary brain cancer in adults. Accumulating studies have reported that long non-coding RNAs (lncRNAs) serve a significant role in the initiation and development of glioma. lncRNA small nucleolar RNA host gene 7 (SNHG7) has been previously demonstrated to serve a role in numerous glioma biological processes, including cell proliferation, invasion and migration. The present study aimed to investigate the role of SNHG7 in glioma through reverse transcription-quantitative PCR, western blotting and cell function assays. The results revealed that SNHG7 expression was upregulated in glioma tissues and cell lines, while microRNA (miR)-138-5p expression was downregulated. Moreover, the knockdown of SNHG7 expression decreased the proliferation of glioma cells. Mechanistic studies demonstrated that SNHG7 downregulated miR-138-5p expression, which subsequently affected the expression levels of its target gene, enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2). In conclusion, the results of the present study suggested that SNHG7 may act as a competing endogenous RNA to sponge miR-138-5p and modulate EZH2 expression. Thus, SNHG7 may enhance glioma proliferation via modulating the miR-138-5p/EZH2 signaling axis.

4.
Sensors (Basel) ; 20(5)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32121475

RESUMO

Normalized cross-correlation is an important mathematical tool in digital signal processing. This paper presents a new algorithm and its systolic structure for digital normalized cross-correlation, based on the statistical characteristic of inner-product. We first introduce a relationship between the inner-product in cross-correlation and a first-order moment. Then digital normalized cross-correlation is transformed into a new calculation formula that mainly includes a first-order moment. Finally, by using a fast algorithm for first-order moment, we can compute the first-order moment in this new formula rapidly, and thus develop a fast algorithm for normalized cross-correlation, which contributes to that arbitrary-length digital normalized cross-correlation being performed by a simple procedure and less multiplications. Furthermore, as the algorithm for the first-order moment can be implemented by systolic structure, we design a systolic array for normalized cross-correlation with a seldom multiplier, in order for its fast hardware implementation. The proposed algorithm and systolic array are also improved for reducing their addition complexity. The comparisons with some algorithms and structures have shown the performance of the proposed method.

5.
Onco Targets Ther ; 12: 11487-11496, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920337

RESUMO

BACKGROUND: Glioma is a common primary brain tumor with extremely poor prognosis outcomes. Increasing evidences have proved the relation between lncRNAs and glioma onset and progression. LncRNA SNHG5 involves in the biological activities of tumor cells, such as proliferation, migration and metastasis. Nevertheless, it is still necessary to explain the molecular mechanism and biofunction of SNHG5 in glioma. MATERIALS AND METHODS: Quantitative real-time PCR (qRT-PCR) was performed to analyze expressions of SNHG5, miR-205-5p and ZEB2 in tumor tissues and cell lines. The cell counting kit-8 (CCK-8) assay, plate and soft agar colony formation assays were performed to evaluate cell proliferation ability. RNA immunoprecipitation assay and dual-luciferase reporter assay were used to confirm the interaction among SNHG5, miR-205-5p and ZEB2. The protein level of ZEB2 was measured by Western blot. RESULTS: Based on our findings, compared with normal tissues, the elevated expression of SNHG5 and decreased expression of miR-205-5p were observed in glioma tissues. The downregulation of SNHG5 exerted an obvious inhibitory effect on glioma cells in terms of their proliferation. With regard to the underlying mechanism, SNHG5 presented a direct inhibitory influence on miR-205-5p which targeted to the 3'-UTR region of zinc finger E-box binding homeobox 2 (ZEB2) mRNA. As a competing endogenous RNA (ceRNA), SNHG5 sponged miR-205-5p, regulating the expression of ZEB2 thereby. CONCLUSION: These discoveries indicate that SNHG5 promotes proliferation of glioma by regulating miR-205-5p/ZEB2 axis.

6.
Biosens Bioelectron ; 118: 160-166, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30075386

RESUMO

Signal-amplified ratiometric electrochemiluminescence (Sa-RECL) provides an attractive approach to maximize signal-to-noise ratio through enhancing signals and eliminate interferences. In this work, we prepared a novel metal-organic framework (MOF)/Au/G-quadruplex as both quenchers and enhancers to fabricate a target-triggered ratiometric ECL sensor for high sensitive and accurate detection of prostatic specific antigen (PSA). The ratiometric ECL sensor using the dual-potential-dependent ECL emitters (quantum dots (QDs) and luminol) and MOF/Au/G-quadruplex not only achieved signal self-calibration but also realized cooperative amplification. After the sequential hybridization among of complementary DNA-QDs, PSA aptamer and pDNA-Au-Hemin-MIL-DNAzyme and the further competition of PSA, the pDNA-Au-Hemin-MIL-DNAzyme probe would keep away from the electrode surface, causing a switchover of their ECL signals from "off-on" state to "on-off" state. The ratiometric ECL aptasensor exhibits high-sensitive and accurate analytical performance toward PSA with a linear detection range from 0.5 to 500 ng mL-1 and a detection limit of 0.058 ng mL-1 (S/N = 3). The novel ratiometric ECL biosensor has been successfully applied to determine different serum samples of PSA, indicating its potential application in the clinical diagnosis.


Assuntos
Técnicas Biossensoriais/métodos , Análise Química do Sangue/métodos , Técnicas Eletroquímicas , Medições Luminescentes , Antígeno Prostático Específico/análise , Antígeno Prostático Específico/sangue , Técnicas Biossensoriais/instrumentação , Análise Química do Sangue/instrumentação , DNA Catalítico , Quadruplex G , Humanos , Masculino , Nanopartículas Metálicas , Pontos Quânticos
7.
Tumour Biol ; 37(2): 2527-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26386721

RESUMO

Metastasis has been one of the major reasons for cancer-related mortality, with multiple genes and pathways being involved in this complex process. Given the molecular variations underlying metastasis of hepatocellular carcinoma (HCC) remains largely unknown; in our previous work, we found copying number of protocadherin-17 (PCDH-17) was significantly deleted in HCC tissues that occurred to metastasize compared with that in the primary HCC without metastasis. Therefore, we hypothesized that PCDH-17 may suppress the metastasis of HCC. There has been, however, no relevant literature available regarding PCDH-17 in HCC. In the present study, we have immunohistochemically detected and clinicopathologically analyzed the expression of PCDH-17 in vivo in clinical tissues; besides, we have explored the role of PCDH-17 ex vivo using a panel of HCC cell lines. It was discovered that PCDH-17 expression was clinically correlated with overall prognosis as well as metastasis in vivo and that PCDH-17 inhibited metastasis via EGFR/MEK/ERK signaling pathway ex vivo. Together, our results obtained both in vivo and ex vivo suggested that activation of EGFR/MEK/ERK signaling pathway through PCDH-17 promotes metastasis in HCC.


Assuntos
Caderinas/genética , Carcinoma Hepatocelular/genética , Movimento Celular/genética , Receptores ErbB/genética , Neoplasias Hepáticas/genética , Sistema de Sinalização das MAP Quinases/genética , Metástase Neoplásica/genética , Animais , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/patologia , Prognóstico , Transdução de Sinais/genética
8.
Appl Opt ; 52(22): 5539-44, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23913076

RESUMO

Phosphor-free dispensing is the most widely used LED packaging method, but this method results in poor quality in angular CCT uniformity. This study proposes a diffuser-loaded encapsulation to solve the problem; the effects of melamine formaldehyde (MF) resin and CaCO3 loaded encapsulation on correlated color temperature (CCT) uniformity and luminous efficiency reduction of the phosphor-converted LEDs are investigated. Results reveal that MF resin loaded encapsulation has better light diffusion performance compared to MF resin loaded encapsulation at the same diffuser concentration, but CaCO3 loaded encapsulation has better luminous efficiency maintenance. The improvements in angular color uniformity for the LEDs emitting with MF resin and CaCO3 loaded encapsulation can be explained by the increase in photon scattering. The utility of this low cost and controllable mineral diffuser packaging method provides a practical approach for enhancing the angular color uniformity of LEDs. The diffuser mass ratio of 1% MF resin or 10% CaCO3 is the optimum condition to obtain low angular CCT variance and high luminous efficiency.

9.
Opt Lett ; 38(13): 2240-3, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23811889

RESUMO

A simple and practical method for preparing phosphor glass is proposed. Phosphor distribution and element analysis are investigated by optical microscope and field emission scanning electron microscope (FE-SEM). The phosphor particles dispersed in the matrix are vividly observed, and their distributions are uniform. Spectrum distribution and color coordinates dependent on the thickness of the screen-printed phosphor layer coupled with a blue light emitting diode (LED) chip are studied. The luminous efficacy of the 75 µm printed phosphor-layer phosphor glass packaged white LED is 81.24 lm/W at 350 mA. This study opens up many possibilities for applications using the phosphor glass on a selected chip in which emission is well absorbed by all phosphors. The screen-printing technique also offers possibilities for the design and engineering of complex phosphor layers on glass substrates. Phosphor screen-printing technology allows the realization of high stability and thermal conductivity for the phosphor layer. This phosphor glass method provides many possibilities for LED packing, including thin-film flip chip and remote phosphor technology.

10.
Chem Commun (Camb) ; 49(54): 6024-6, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23598712

RESUMO

Platinum nanotubes (PtNTs) exhibiting high porosity were constructed by sacrificing the exterior of tellurium nanowires (TeNWs) and disintegrating the inner part spontaneously in aqueous solution at room temperature, in which the Kirkendall effect may play an important role. The present PtNTs exhibited intrinsic peroxidase-like activity in the presence of H2O2.


Assuntos
Materiais Biocompatíveis/síntese química , Nanotubos/química , Materiais Biocompatíveis/metabolismo , Catálise , Peróxido de Hidrogênio/química , Cinética , Nanofios/química , Peroxidase/metabolismo , Platina/química , Porosidade , Telúrio/química , Temperatura , Água/química
11.
Appl Opt ; 52(10): 2075-9, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23545962

RESUMO

An advanced phosphor conformal coating technology is proposed, good correlated color temperature (CCT) and chromaticity uniformity samples are fabricated through phosphor spray painting technology. Spray painting technology is also suitable for phosphor conformal coating of whole LED wafers. The samples of different CCTs are obtained through controlling the phosphor film thickness in the range of 6-80 µm; CCT variation of samples can be controlled in the range of ±200 K. The experimental Δuv reveals that the spray painting method can obtain a much smaller CCT variation (Δuv of 1.36e(-3)) than the conventional dispensing method (Δuv of 11.86e(-3)) when the light is emitted at angles from -90° to +90°, and chromaticity area uniformity is also improved significantly.

12.
Zhonghua Wei Chang Wai Ke Za Zhi ; 15(10): 1070-2, 2012 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-23099909

RESUMO

OBJECTIVE: To explore the feasibility and safety of abdominosacral resection for patients with locally advanced primary low rectal cancer. METHODS: A total of 97 low rectal cancer patients were amenable to surgery but not anal sphincter preservation were included in this study and divided into the abdominoperineal resection group(n=49) and abdominosacral resection group(n=48) according to the order of alternative admission time between June 2010 and January 2012. Intraoperative and postoperative parameters were compared between the two groups. RESULTS: The surgery went well and no perioperative mortality in the two groups. Compared with abdominoperineal resection group, the operative time of abdominosacral resection group(including the 2nd position adjustment time) was longer[(188±45) min vs. (143±48) min, P=0.000], the unexpected prostate or vagina injury incidence was lower [0 vs. 14.3%(7/49), P=0.032), and the perineal wound infection rate was lower [2.1% (1/48) vs. 18.4% (9/49), P=0.040]. CONCLUSION: Abdominosacral excision is feasible and safe for patients with locally advanced primary low rectal cancer.


Assuntos
Abdome/cirurgia , Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório , Humanos , Períneo , Resultado do Tratamento
13.
Clin Vaccine Immunol ; 19(12): 1916-20, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23015648

RESUMO

Toxoplasma gondii is an obligate intracellular parasite infecting humans and other warm-blooded animals, resulting in serious public health problems and economic losses worldwide. Rhoptries are involved in T. gondii invasion and host cell interaction and have been implicated as important virulence factors. In the present study, a DNA vaccine expressing rhoptry protein 13 (ROP13) of T. gondii inserted into eukaryotic expression vector pVAX I was constructed, and the immune protection it induced in Kunming mice was evaluated. Kunming mice were immunized intramuscularly with pVAX-ROP13 and/or with interleukin-18 (IL-18). Then, we evaluated the immune response using a lymphoproliferative assay, cytokine and antibody measurements, and the survival times of mice challenged with the virulent T. gondii RH strain (type I) and the cyst-forming PRU strain (type II). The results showed that pVAX-ROP13 alone or with pVAX/IL-18 induced a high level of specific anti-T. gondii antibodies and specific lymphocyte proliferative responses. Coinjection of pVAX/IL-18 significantly increased the production of gamma interferon (IFN-γ), IL-2, IL-4, and IL-10. Further, challenge experiments showed that coimmunization of pVAX-ROP13 with pVAX/IL-18 significantly (P < 0.05) increased survival time (32.3 ± 2.7 days) compared with pVAX-ROP13 alone (24.9 ± 2.3 days). Immunized mice challenged with T. gondii cysts (strain PRU) had a significant reduction in the number of brain cysts, suggesting that ROP13 could trigger a strong humoral and cellular response against T. gondii cyst infection and that it is a potential vaccine candidate against toxoplasmosis, which provided the foundation for further development of effective vaccines against T. gondii.


Assuntos
Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Toxoplasma/imunologia , Vacinas de DNA/imunologia , Fatores de Virulência/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Encéfalo/parasitologia , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Expressão Gênica , Vetores Genéticos , Injeções Intramusculares , Leucócitos Mononucleares/imunologia , Camundongos , Carga Parasitária , Plasmídeos , Proteínas de Protozoários/genética , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/genética , Toxoplasma/genética , Toxoplasmose/parasitologia , Toxoplasmose/prevenção & controle , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Fatores de Virulência/genética
14.
BMC Genomics ; 13: 374, 2012 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-22863187

RESUMO

BACKGROUND: Fusarium wilt, caused by the fungal pathogen Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), is considered the most lethal disease of Cavendish bananas in the world. The disease can be managed in the field by planting resistant Cavendish plants generated by somaclonal variation. However, little information is available on the genetic basis of plant resistance to Foc TR4. To a better understand the defense response of resistant banana plants to the Fusarium wilt pathogen, the transcriptome profiles in roots of resistant and susceptible Cavendish banana challenged with Foc TR4 were compared. RESULTS: RNA-seq analysis generated more than 103 million 90-bp clean pair end (PE) reads, which were assembled into 88,161 unigenes (mean size = 554 bp). Based on sequence similarity searches, 61,706 (69.99%) genes were identified, among which 21,273 and 50,410 unigenes were assigned to gene ontology (GO) categories and clusters of orthologous groups (COG), respectively. Searches in the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG) mapped 33,243 (37.71%) unigenes to 119 KEGG pathways. A total of 5,008 genes were assigned to plant-pathogen interactions, including disease defense and signal transduction. Digital gene expression (DGE) analysis revealed large differences in the transcriptome profiles of the Foc TR4-resistant somaclonal variant and its susceptible wild-type. Expression patterns of genes involved in pathogen-associated molecular pattern (PAMP) recognition, activation of effector-triggered immunity (ETI), ion influx, and biosynthesis of hormones as well as pathogenesis-related (PR) genes, transcription factors, signaling/regulatory genes, cell wall modification genes and genes with other functions were analyzed and compared. The results indicated that basal defense mechanisms are involved in the recognition of PAMPs, and that high levels of defense-related transcripts may contribute to Foc TR4 resistance in banana. CONCLUSIONS: This study generated a substantial amount of banana transcript sequences and compared the defense responses against Foc TR4 between resistant and susceptible Cavendish bananas. The results contribute to the identification of candidate genes related to plant resistance in a non-model organism, banana, and help to improve the current understanding of host-pathogen interactions.


Assuntos
Fusarium/patogenicidade , Perfilação da Expressão Gênica/métodos , Musa/microbiologia , Raízes de Plantas/microbiologia , Doenças das Plantas/microbiologia
15.
Cancer Invest ; 27(2): 163-70, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19235588

RESUMO

Lupeol (Lup-20(29)-en-3H-ol), a novel dietary triterpene, was found in fruits, vegetables, and several medicinal plants. Here, we investigated its growth-inhibitory effect and associated mechanisms in hepatocellular carcinoma SMMC7721 cells. Lupeol treatment resulted in significant inhibition of cell viability in a dose-dependent manner and caused apoptotic death of this cell line with activation of caspase3 expression. Caspase8 inhibitor pretreatment was found to partially block the apoptosis induced by Lupeol. Moreover, Lupeol specifically caused a significant decrease in the expression of Death receptor 3 (DR3) mRNA and protein and a significant elevated expression of FADD mRNA whereas Fas mRNA and protein expression was not detectable. Further more, knockdown of DR3 by small interfering RNA inhibited the growth and induced apoptosis of hepatocellular carcinoma cell. These results suggested that Lupeol treatment induced growth inhibition and apoptosis in SMMC7721 cells, the mechanism is due to down-regulation of DR3 expression. We demonstrated that Lupeol appears to be a promising chemopreventive agent for treating hepatocellular carcinoma, and DR3 may be an important target for liver cancer therapy.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Hepáticas/tratamento farmacológico , Membro 25 de Receptores de Fatores de Necrose Tumoral/antagonistas & inibidores , Triterpenos/farmacologia , Caspase 3/análise , Caspase 8/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteína de Domínio de Morte Associada a Fas/genética , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Triterpenos Pentacíclicos , RNA Mensageiro/análise , Membro 25 de Receptores de Fatores de Necrose Tumoral/análise , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética
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