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1.
Plant Cell ; 31(1): 250-271, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30464035

RESUMO

Remodeling of auxin distribution during the integration of plant growth responses with the environment requires the precise control of auxin influx and efflux transporters. The plasma membrane-localized PIN-FORMED (PIN) proteins facilitate auxin efflux from cells, and their activity is regulated by reversible phosphorylation. How PIN modulates plant cellular responses to external stresses and whether its activity is coordinated by phospholipids remain unclear. Here, we reveal that, in Arabidopsis (Arabidopsis thaliana), the phosphatidic acid (PA)-regulated PINOID (PID) kinase is a crucial modulator of PIN2 activity and auxin redistribution in response to salt stress. Under salt stress, loss of phospholipase D function impaired auxin redistribution and resulted in markedly reduced primary root growth; these effects were reversed by exogenous PA. The phospholipase D-derived PA interacted with PID and increased PID-dependent phosphorylation of PIN2, which activated auxin efflux and altered auxin accumulation, promoting root growth when exposed to salt stress. Ablation of the PA binding motif not only diminished PID accumulation at the plasma membrane but also abolished PA-promoted PID phosphorylation of PIN2 and its function in coping with salt stress; however, this ablation did not affect inflorescence and cotyledon development or PIN2-dependent gravitropic and halotropic responses. Our data indicate a role for PA in coupling extracellular salt signaling to PID-directed PIN2 phosphorylation and polar auxin transport, highlighting the importance of lipid-protein interactions in the spatiotemporal regulation of auxin signaling.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ácidos Fosfatídicos/farmacologia , Raízes de Plantas/metabolismo , Arabidopsis/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Fosforilação/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Estresse Salino , Transdução de Sinais/efeitos dos fármacos
2.
J Cell Mol Med ; 24(10): 5751-5757, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32285549

RESUMO

The aim of this study was to investigate in vitro magnetic resonance imaging (MRI) of PDAC using ENO1-targeted superparamagnetic iron oxide nanoparticles and xenograft models. Expression level and location of ENO1 protein in pancreatic cancer cell lines of CFPAC-1 and MiaPaCa-2 were detected by Western blotting, flow cytometry and confocal microscopy. Dex-g-PCL/SPIO nanoparticles targeting ENO1 were constructed with ENO1 antibody and characterized by MRI. In addition, ENO1-Dex-g-PCL/SPIO nanoparticles were tested to assess their efficacy on the detection of PDAC using in vitro and in vivo MRI. The results showed that ENO1 was expressed in both human PDAC cell lines of CFPAC-1 and MiaPaCa-2, demonstrating that the localization of cytoplasm and membrane was dominant. It was confirmed that ENO1 antibody was connected to the SPIO surface in ENO1-Dex-g-PCL/SPIO nanoparticles. The nanoparticles had satisfactory superparamagnetism and significantly enhance the detection of PDAC by in vivo and in vitro MRI. In conclusion, ENO1 can serve as a membrane protein expressed on human PDAC cell lines. ENO1-targeted SPIO nanoparticles using ENO1 antibody can increase the efficiency of detection of PDAC by in vitro and in vivo MRI.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro/química , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico , Fosfopiruvato Hidratase/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Linhagem Celular Tumoral , Dextranos/química , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/ultraestrutura , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Pancreáticas/patologia , Poliésteres/química
3.
J Cell Biochem ; 120(3): 4214-4224, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30520138

RESUMO

Chronic intermittent hypoxia (CIH) in obstructive sleep apnea causes damage of aortic endothelial cells, which predisposes the development of many cardiovascular diseases. Recently, both altered expression of microRNAs (miRNAs) and impaired autophagy were found to be associated with endothelial cell dysfunction in CIH. However, the exact molecular regulatory pathway has not been determined. Here, we address this question. In a mouse model of CIH, we detected significant upregulation of miR-30a, a miRNA that targets 3'-untranslated region of autophagy-associated protein 6 (Beclin-1) messenger RNA (mRNA) for suppressing the protein translation, which subsequently attenuated the endothelial cell autophagy against cell death. Indeed, unlike Beclin-1 mRNA, the Beclin-1 protein in endothelial cells did not increase after CIH. Suppression of miR-30a by expression of antisense of miR-30a significantly increased Beclin-1 levels to enhance endothelial cell autophagy in vitro and in vivo, which improved endothelial cell survival against CIH. Together, these data suggest that endothelial cell autophagy in CIH may be attenuated by miR-30a-mediated translational control of Beclin-1 as an important cause of endothelial cell dysfunction and damage.


Assuntos
Autofagia/genética , Proteína Beclina-1/metabolismo , Células Endoteliais/metabolismo , Hipóxia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Biossíntese de Proteínas , Regiões 3' não Traduzidas , Animais , Apoptose/genética , Hipóxia Celular , Sobrevivência Celular/genética , Células Cultivadas , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro , Transdução Genética , Transfecção
4.
Chin Med Sci J ; 30(2): 65-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26148994

RESUMO

OBJECTIVE: To explore the relationship between ulcerative colitis (UC) and lung injuries by assessing their clinical manifestations and characteristics. METHODS: From July 2009 to April 2012, 91 UC patients presenting to Longhua Hospital who met the established inclusion and exclusion criteria were enrolled in this retrospective study. According to the scores of disease activity index, the patients were divided into the mild, moderate, and severe groups. Meanwhile, the records of pulmonary symptoms, chest X-ray image, and pulmonary function were reviewed. RESULTS: Sixty-eight (74.7%) patients had at least 1 pulmonary symptom, such as cough (38.5%), shortness of breath (27.5%), and expectoration (17.6%). And 77 (84.6%) had at least 1 ventilation abnormality. Vital capacity value was significantly lower in the severe group than that in the mild group (91.82%±10.38% vs. 98.92%±12.12%, P<0.05). CONCLUSIONS: Lung injury is a common extraintestinal complication of UC. According to the theory in Traditional Chinese Medicine that the lung and large intestine are related, both the lungs and large intestine should be treated simultaneously.


Assuntos
Colite Ulcerativa/complicações , Lesão Pulmonar/etiologia , Adulto , Colite Ulcerativa/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Capacidade Vital
5.
Math Biosci Eng ; 19(5): 4703-4718, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35430836

RESUMO

Purpose: Due to the complex distribution of liver tumors in the abdomen, the accuracy of liver tumor segmentation cannot meet the needs of clinical assistance yet. This paper aims to propose a new end-to-end network to improve the segmentation accuracy of liver tumors from CT. Method: We proposed a hybrid network, leveraging the residual block, the context encoder (CE), and the Attention-Unet, called ResCEAttUnet. The CE comprises a dense atrous convolution (DAC) module and a residual multi-kernel pooling (RMP) module. The DAC module ensures the network derives high-level semantic information and minimizes detailed information loss. The RMP module improves the ability of the network to extract multi-scale features. Moreover, a hybrid loss function based on cross-entropy and Tversky loss function is employed to distribute the weights of the two-loss parts through training iterations. Results: We evaluated the proposed method in LiTS17 and 3DIRCADb databases. It significantly improved the segmentation accuracy compared to state-of-the-art methods. Conclusions: Experimental results demonstrate the satisfying effects of the proposed method through both quantitative and qualitative analyses, thus proving a promising tool in liver tumor segmentation.


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias Hepáticas , Atenção , Progressão da Doença , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Redes Neurais de Computação , Tomografia Computadorizada por Raios X
6.
J Nanosci Nanotechnol ; 11(3): 1996-2002, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21449339

RESUMO

MnO2/CNT composite nanotubes with nanometer-sized flake-like MnO2 on carbon nanotubes' surfaces have been synthesized through an easy and efficient solution-based method. Similarly, Mn3O4/CNT composite nanotubes have also been synthesized by using the same method but different heat treatment process. The structures and compositions of the two types of composite nanotubes are characterized by using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption isotherms. Electrochemical measurements indicate that the MnO2/CNT composites nanotubes exhibit significantly enhanced supercapacitance performance compared with the Mn3O4/CNT composite nanotubes, the as-synthesized MnO2 nanoparticles and commercial MnO2. The possibilities of the enhanced properties are illustrated on the basis of analysis of XRD and X-ray photoelectron spectroscopy measurements. Our results presented here can give clear evidence of the superiority of nanocrystalline MnO2 to nanocrystalline Mn3O4 toward the applications as electrode materials in electrochemical capacitors.


Assuntos
Cristalização/métodos , Capacitância Elétrica , Eletrodos , Compostos de Manganês/química , Nanotubos de Carbono/química , Óxidos/química , Eletroquímica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Substâncias Macromoleculares/síntese química , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
7.
Aging (Albany NY) ; 13(15): 19272-19281, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34374662

RESUMO

Recent studies focus on long noncoding RNAs (lncRNA) as crucial regulators of cancer biology that contribute to essential cancer cell functions such as cell proliferation, apoptosis, and metastasis. In pancreatic cancer, several lncRNAs have been mentioned as important actors in tumorigenesis. However, the function of lncRNA ANRIL (named as ANRIL as follows) in pancreatic cancer has not been elucidated. In the present study, we show that ANRIL was up-regulated while miR-181a was down-regulated in pancreatic cancer tissues and HMGB1 was highly expressed. Knockdown of ANRIL in pancreatic cancer repressed cellular proliferation, invasion, migration, and reduced chemotherapy resistance to gemcitabine. ANRIL was negatively correlated with miR-181a, while overexpression of miR-181a could reverse the effect. For further mechanism research, we found that miR-181a aimed to HMGB1 which activated cell autophagy. Taken together, our results implicate that the ANRIL, by targeting miR-181a, activates the HMGB1-induced cell autophagy, which is thought to be critical for oncogenesis.


Assuntos
Autofagia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína HMGB1/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética , Apoptose , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Regulação para Baixo , Proteína HMGB1/metabolismo , Humanos , MicroRNAs/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , RNA Longo não Codificante/metabolismo , Gencitabina
8.
J Int Med Res ; 48(4): 300060519865368, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31856624

RESUMO

OBJECTIVE: To observe the effects of glutaminase (GLS) inhibitors on autophagy and proliferation of pancreatic stellate cells, and to explore their functions in pancreatic cancer. METHODS: Pancreatic cancer cells were divided into two groups. Group A was the control untreated group, and group B cells were treated with GLS inhibitors. Western blotting was used to detect the expression of Atg5, Bcl-2, Bax, and Bid proteins. The bromodeoxyuridine assay and scratch test were employed to investigate cell proliferation and invasion, respectively. The expression of E-cadherin, vimentin, cell adhesion molecule 2 (CADM2), and Snail protein was investigated by immunofluorescence. RESULTS: The expression of Atg5, Bax, and Bid was higher in group A than in group B, while Bcl-2 expression was lower in group A than in group B. Group A cells demonstrated greater proliferation and invasion than group B cells. The expression of E-cadherin was lower in group A cells than group B cells, while vimentin, CADM2, and Snail were expressed at higher levels in group A than group B cells. CONCLUSION: The inhibition of glutamine isozymes reduces autophagy and apoptosis in astrocytes, and inhibits pancreatic cancer cell proliferation and metastasis, while reducing their invasiveness.


Assuntos
Neoplasias Pancreáticas , Células Estreladas do Pâncreas , Apoptose , Autofagia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Glutamatos , Humanos , Neoplasias Pancreáticas/genética
9.
Plant Sci ; 290: 110298, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31779909

RESUMO

Phospholipase D (PLD) hydrolyzes the phosphodiester bond of glycerophospholipids to yield phosphatidic acid (PA) and a free headgroup. PLDs are important for plant growth, development, and responses to external stresses. However, their roles in triacylglycerol (TAG) synthesis are still unclear. Here, we report that a soybean (Glycine max) PLDγ (GmPLDγ) is involved in glycerolipid turnover and seed oil production. GmPLDγ was targeted to mitochondria and exhibited PLD activity that was activated by oleate and phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2]. Overexpression of GmPLDγ (abbreviated GmPLDγ-OE) in Arabidopsis thaliana resulted in enhanced seed weight, elevated levels of TAGs with 18-, 20-, and 22-carbon fatty acids (FAs), and altered oil-body morphology. Furthermore, the levels of membrane lipids in vegetative tissues decreased significantly, whereas no overt changes were found in mature seeds except for a decrease in the digalactosyldiacylglycerol (DGDG) level in the GmPLDγ-OE lines. Additionally, the expression of genes involved in glycerolipid metabolism was significantly upregulated in developing siliques in GmPLDγ-OE lines. Together, our data indicate a regulatory role for GmPLDγ in TAG synthesis and fatty-acid remodeling, highlighting the importance of mitochondria-directed glycerophospholipid homeostasis in seed oil accumulation.


Assuntos
Arabidopsis/metabolismo , Ácidos Graxos/metabolismo , Regulação da Expressão Gênica de Plantas , Glycine max/genética , Fosfolipase D/genética , Óleos de Plantas/metabolismo , Proteínas de Plantas/genética , Arabidopsis/genética , Fosfolipase D/metabolismo , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Sementes/metabolismo , Glycine max/metabolismo
10.
Am J Transl Res ; 11(7): 4470-4480, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396350

RESUMO

Resistance to Gemcitabine (GEM) is a crucial problem in treatment of pancreatic cancer. Many studies indicate the direct impact of glycolytic enzyme on chemoresistance. However, it still has not been known whether Enolase 1 (ENO1), a multifunctional glycolytic enzyme, is a potential target to overcome GEM resistance in pancreatic ductal adenocarcinoma (PDAC). In this study, we showed that ENO1 high expression was associated with poor prognosis of PDAC patients. Moreover, we investigated the impacts of ENO1 silencing on hypoxia induced GEM chemoresistance in CFPAC-1 and MiaPaCa-2 cells. The results showed that, targeting ENO1 using ENO1-shRNA could sensitize hypoxia induced chemoresistance in pancreatic cancer cells by modulation of redox homeostasis, the mechanisms appear to be associated with influences on proliferation, apoptosis, and cell cycle regulated by increased intracellular reactive oxygen species (ROS). We demonstrated that targeting ENO1 could be a potential strategy for overcoming hypoxia induced GEM chemoresistance in PDAC cells.

11.
Comput Assist Surg (Abingdon) ; 24(sup2): 20-26, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31401890

RESUMO

Liver segmentation from CT is regarded as a prerequisite for computer-assisted clinical applications. However, automatic liver segmentation technology still faces challenges due to the variable shapes and low contrast. In this paper, a patient-specific probabilistic atlas (PA)-based method combing modified distance regularized level set for liver segmentation is proposed. Firstly, the similarities between training atlases and testing patient image are calculated, resulting in a series of weighted atlas, which are used to generate the patient-specific PA. Then, a most likely liver region (MLLR) can be determined based on the patient-specific PA. Finally, the refinement is performed by the modified distance regularized level set model, which takes advantage of both edge and region information as balloon force. We evaluated our proposed scheme based on 35 public datasets, and experimental result shows that the proposed method can be deployed for robust and precise liver segmentation, to replace the tedious and time-consuming manual method.


Assuntos
Imageamento Tridimensional/métodos , Fígado/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Algoritmos , Anatomia Transversal/métodos , Conjuntos de Dados como Assunto , Humanos , Modelos Anatômicos
12.
J Plant Physiol ; 242: 153019, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437808

RESUMO

Acyl-CoA:diacylglycerol acyltransferase (DGAT) is a key enzyme in the Kennedy pathway of triacylglycerol (TAG) synthesis. It catalyzes the acyl-CoA-dependent acylation of sn-1, 2-diacylglycerol to form TAG. DGATs in soybean (Glycine max) have been reported, but their functions are largely unclear. Here we cloned three members of DGAT1 and four members of DGAT2 family from soybean, named GmDGAT1A to GmDGAT1C, and GmDGAT2A to GmDGAT2D, respectively. GmDGAT1A and GmDGAT1C were expressed at a high level in immature seeds, GmDGAT2B in mature seeds, and GmDGAT2C in older leaves. The seven genes were transformed into the H1246 quadruple mutant yeast strain, in which GmDGAT1A, GmDGAT1B, GmDGAT1C, GmDGAT2A, and GmDGAT2B had the ability to produce TAG. Six genes were transformed into Arabidopsis respectively, and constitutive expression of GmDGAT1A and GmDGAT1B resulted in an increase in oil content at the cost of reduced protein content in seeds. Overexpression of GmDGAT1A produced heavier weight of individual seed, but did not affect the weight of total seeds from a plant. Our results reveal the functions of soybean DGATs in seed oil synthesis using transgenic Arabidopsis. The implications for the biotechnological modification of the oil contents in soybeans by altering DGAT expression are discussed.


Assuntos
Arabidopsis/metabolismo , Diacilglicerol O-Aciltransferase/genética , Glycine max/enzimologia , Óleos de Plantas/metabolismo , Triglicerídeos/biossíntese , Arabidopsis/genética , Diacilglicerol O-Aciltransferase/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Genômica , Filogenia , Plantas Geneticamente Modificadas/metabolismo , Sementes/genética , Sementes/metabolismo , Glycine max/metabolismo , Triglicerídeos/metabolismo
13.
Trials ; 19(1): 355, 2018 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-29973284

RESUMO

BACKGROUND: Over the past two or three decades, the prevalence of asthma has significantly increased worldwide; therefore, effective treatment without side effects is of utmost importance. Traditional Chinese medicine (TCM) plays a vital role in reducing symptoms and improving the quality of life in persistent-asthma patients. The aim of this study is to evaluate the efficacy of the Jia Wei Yang He (JWYH) formula in the treatment of asthma and to explore the relationship between the airway microbiome and TCM treatment in asthma patients. METHODS/DESIGN: This multicenter, parallel-arm, randomized, double-blinded, placebo-controlled trial will assess the efficacy of JWYH in asthma patients with usual care. Persistent-asthma patients without life-threatening disease will be enrolled on a random basis and are equally assigned to a high- or a low-dose JWYH plus usual care group, or a placebo plus usual care group. Patients are followed up for 4 months. Accordingly, 240 patients will yield sufficient statistical power to determine a difference between groups. Based on modified intent-to-treat (mITT) analyses, the three groups will be compared at 4 weeks after the beginning of treatment. The primary efficacy measurement is the mean change in the Asthma Control Test (ACT) score from baseline to 4 weeks post treatment. Secondary outcomes include forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), and asthma exacerbations. This trial also includes analyses of the associations between airway microbiome and asthma treatment. DISCUSSION: In this study, a randomized clinical trial design is described. The results are based on several outcomes that estimate the efficacy of the JWYH formula and prospective links between the airway microbiome and asthma treatment. TRIAL REGISTRATION: ClinicalTrials.gov, ID: NCT03299322 . Registered on 3 October 2017.


Assuntos
Asma/tratamento farmacológico , Medicina Tradicional Chinesa , Ensaios Clínicos Controlados Aleatórios como Assunto , Asma/fisiopatologia , Método Duplo-Cego , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Pulmão/microbiologia , Pulmão/fisiopatologia , Medicina Tradicional Chinesa/efeitos adversos , Microbiota , Estudos Multicêntricos como Assunto , Controle de Qualidade , Tamanho da Amostra
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