Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
J Nanobiotechnology ; 22(1): 110, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481281

RESUMO

BACKGROUND: Breast cancer ranks first among malignant tumors, of which triple-negative breast cancer (TNBC) is characterized by its highly invasive behavior and the worst prognosis. Timely diagnosis and precise treatment of TNBC are substantially challenging. Abnormal tumor vessels play a crucial role in TNBC progression and treatment. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis, while effective NO delivery can normalize the tumor vasculature. Accordingly, we have proposed here a tumor vascular microenvironment remodeling strategy based on NO-induced vessel normalization and extracellular matrix collagen degradation with multimodality imaging-guided nanoparticles against TNBC called DNMF/PLGA. RESULTS: Nanoparticles were synthesized using a chemotherapeutic agent doxorubicin (DOX), a NO donor L-arginine (L-Arg), ultrasmall spinel ferrites (MnFe2O4), and a poly (lactic-co-glycolic acid) (PLGA) shell. Nanoparticle distribution in the tumor was accurately monitored in real-time through highly enhanced magnetic resonance imaging and photoacoustic imaging. Near-infrared irradiation of tumor cells revealed that MnFe2O4 catalyzes the production of a large amount of reactive oxygen species (ROS) from H2O2, resulting in a cascade catalysis of L-Arg to trigger NO production in the presence of ROS. In addition, DOX activates niacinamide adenine dinucleotide phosphate oxidase to generate and supply H2O2. The generated NO improves the vascular endothelial cell integrity and pericellular contractility to promote vessel normalization and induces the activation of endogenous matrix metalloproteinases (mainly MMP-1 and MMP-2) so as to promote extravascular collagen degradation, thereby providing an auxiliary mechanism for efficient nanoparticle delivery and DOX penetration. Moreover, the chemotherapeutic effect of DOX and the photothermal effect of MnFe2O4 served as a chemo-hyperthermia synergistic therapy against TNBC. CONCLUSION: The two therapeutic mechanisms, along with an auxiliary mechanism, were perfectly combined to enhance the therapeutic effects. Briefly, multimodality image-guided nanoparticles provide a reliable strategy for the potential application in the fight against TNBC.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Óxido Nítrico , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio , Doxorrubicina/farmacologia , Fototerapia/métodos , Colágeno , Linhagem Celular Tumoral , Microambiente Tumoral
2.
Plant Physiol Biochem ; 205: 108137, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37977027

RESUMO

Drought and salt stress are major environmental conditions that severely limit plant growth and productivity. WRKY transcription factors play a vital role in the responses against biotic or abiotic stress. In this study, TaWRKY24, a gene of the IIe WRKY family identified in wheat, was cloned and characterized. TaWRKY24 was mainly expressed in wheat leaf and stem and induced by treatment with PEG6000, salt, H2O2, ABA, MeJA, and ethrel. TaWRKY24 transient expression in onion epidermal cells suggested its nuclear localization and its transcriptional activation capability characteristics. Overexpression of TaWRKY24 in tobacco improved the seed germination rate and root growth of seedlings in transgenic lines when subjected to higher mannitol and NaCl concentrations. Further research showed that transgenic lines had higher proline and soluble sugars and lower levels of reactive oxygen species (ROS) and malondialdehyde (MDA). Moreover, compared to normal and negative control plants, TaWRKY24 silenced wheat seedlings had reduced growth under salt and drought stress. This study shows that wheat TaWRKY24 is crucial to plant stress, providing an excellent candidate gene for wheat resistance breeding.


Assuntos
Tolerância ao Sal , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Triticum/metabolismo , Peróxido de Hidrogênio/metabolismo , Secas , Melhoramento Vegetal , Estresse Fisiológico , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Int J Gen Med ; 16: 5449-5465, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38021066

RESUMO

Background: Lung adenocarcinoma (LUAD) has high morbidity and mortality. Current studies indicate nucleoporin 107 (NUP107) is involved in the construction of nuclear pore complex, and NUP107 overexpression contributes to the growth and development in most types of cancers, but its effect in LUAD has not been elucidated. Methods: Differences in NUP107 expression were investigated using the Cancer Genome Atlas (TCGA) and multiple Gene Expression Omnibus (GEO) data sets. Enrichment analysis were implemented to probe the NUP107 function. The association of NUP107 with the degree of immune cell infiltration was investigated by the TIMER database, single-sample gene set enrichment analysis (ssGSEA), and ESTIMATE. The association of NUP107 expression with tumor mutation burden (TMB), TP53, and immune checkpoint was analyzed. Single-cell RNA sequencing data were used to detect NUP107 expression in different cell clusters. Finally, we performed real-time quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC) to prove the difference of NUP107 expression. Results: NUP107 was overexpressed in LUAD and mainly expressed in cancer stem cell (CSC). Overexpression of NUP107 in LUAD suggested a poorer prognosis. Functional enrichment analysis pointed out that NUP107 was mainly linked to the regulation of cell cycle. Both immune cell infiltration and TMB were found to be in connection with NUP107. Cases in the group with high NUP107 expression had poorer immune infiltration, but had higher expression of immune checkpoints, TMB, and proportion of TP53 mutations. Conclusion: NUP107 is a sensitive diagnostic and prognostic factor for LUAD and may be involved in tumor progression through its effects on cell cycle and immune infiltration.

4.
Plant Physiol Biochem ; 203: 108009, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37696193

RESUMO

ETHYLENE INSENSITIVE 2 (EIN2), as the core component of the ethylene signaling pathway, can widely regulate plant growth, development, and stress responses. However, the comprehensive study and function of EIN2 in wheat Cadmium (Cd) stress remain largely unexplored. Here, we identified 33 EIN2 genes and designated as TaEIN2-2B to TaEIN2-Un.3 in Triticum aestivum. The analysis of cis-regulatory elements in promoter regions and RNA-Seq showed that TaEIN2s were functionally related to plant growth and development, as well as the response to biotic and abiotic stress. qRT-PCR analysis of TaEIN2s indicated their sensitivity to Cd stress. Compared with WT plants, TaEIN2-4D.1-RNAi transgenic wheat lines showed enhanced shoot and root elongation, dry weight and chlorophyll accumulation, together with a reduced accumulation of Cd in wheat grain. In addition, TaEIN2-4D.1-RNAi transgenic wheat lines showed enhanced Reactive Oxygen Species (ROS) scavenging capacity compared with WT plants. In conclusion, our research indicates that TaEIN2 plays a key role in response to cadmium stress in wheat, which provides valuable information for crop improvement.

5.
Front Bioeng Biotechnol ; 11: 1174206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37113672

RESUMO

Hypoxia is one of the major causes of cancer resistance and metastasis. Currently, it is still lack of convenient ways to simulate the in vivo hypoxic tumor microenvironment (TME) under normoxia in vitro. In this study, based on multi-polymerized alginate, we established a three-dimensional culture system with a core-shell structure (3d-ACS), which prevents oxygen diffusion to a certain extent, thereby simulating the hypoxic TME in vivo. The cell activity, hypoxia inducible factor (HIF) expression, drug resistance, and the related gene and protein changes of the gastric cancer (GC) cells were investigated in vitro and in vivo. The results demonstrated that the GC cells formed organoid-like structures in the 3d-ACS and manifested more aggressive growth and decreased drug responses. Our study provides an accessible hypoxia platform in the laboratory with moderate configuration and it may be applied in studies of the hypoxia-induced drug resistances and other preclinical fields.

6.
Front Endocrinol (Lausanne) ; 13: 967062, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111297

RESUMO

Objectives: To determine the predictors of axillary lymph node metastasis (ALNM), two nomogram models were constructed to accurately predict the status of axillary lymph nodes (ALNs), mainly high nodal tumour burden (HNTB, > 2 positive lymph nodes), low nodal tumour burden (LNTB, 1-2 positive lymph nodes) and negative ALNM (N0). Accordingly, more appropriate treatment strategies for breast cancer patients without clinical ALNM (cN0) could be selected. Methods: From 2010 to 2015, a total of 6314 patients with invasive breast cancer (cN0) were diagnosed in the Surveillance, Epidemiology, and End Results (SEER) database and randomly assigned to the training and internal validation groups at a ratio of 3:1. As the external validation group, data from 503 breast cancer patients (cN0) who underwent axillary lymph node dissection (ALND) at the Second Affiliated Hospital of Chongqing Medical University between January 2011 and December 2020 were collected. The predictive factors determined by univariate and multivariate logistic regression analyses were used to construct the nomograms. Receiver operating characteristic (ROC) curves and calibration plots were used to assess the prediction models' discrimination and calibration. Results: Univariate analysis and multivariate logistic regression analyses showed that tumour size, primary site, molecular subtype and grade were independent predictors of both ALNM and HNTB. Moreover, histologic type and age were independent predictors of ALNM and HNTB, respectively. Integrating these independent predictors, two nomograms were successfully developed to accurately predict the status of ALN. For nomogram 1 (prediction of ALNM), the areas under the receiver operating characteristic (ROC) curve in the training, internal validation and external validation groups were 0.715, 0.688 and 0.876, respectively. For nomogram 2 (prediction of HNTB), the areas under the ROC curve in the training, internal validation and external validation groups were 0.842, 0.823 and 0.862. The above results showed a satisfactory performance. Conclusion: We established two nomogram models to predict the status of ALNs (N0, 1-2 positive ALNs or >2 positive ALNs) for breast cancer patients (cN0). They were well verified in further internal and external groups. The nomograms can help doctors make more accurate treatment plans, and avoid unnecessary surgical trauma.


Assuntos
Neoplasias da Mama , Metástase Linfática , Segunda Neoplasia Primária , Feminino , Humanos , Axila/patologia , Neoplasias da Mama/patologia , Metástase Linfática/patologia , Nomogramas , Biópsia de Linfonodo Sentinela
7.
Int J Biol Macromol ; 215: 665-674, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35777510

RESUMO

The traditional 2d culture has been proved inferior to reproduce the subtle interaction between cell-to-cell and cell-to-extracellular matrix (ECM) in tumor microenvironment (TME) and collagen in ECM contributes to various malignancies of tumors. Hence, the 3d model contained with collagen may overcome the shortcomings of 2d culture. In this study, the in vitro TME mimicking matrix was prepared by coupling porcine liver-derived collagen (COL) and the dialdehyde group of partially oxidized alginate (OA), namely OA-COL, and the 3d OA-COL droplets were polymerized by divalent calcium ions. In the 3d OA-COL droplets, cancer cells displayed vigorous proliferation, and the cells grew in clusters and formed a unique spindle like clone. Quantitative analysis proved that various gene transcription and protein expression were up-regulated for the cells in the 3d OA-COL droplets, including F-actin reassembling, focal adhesion, pseudopodia formation, and the proteins involved in epithelial-to-mesenchymal transition (EMT). The 3d OA-COL droplets induced the cells with strengthened polarity, invasiveness, higher IC50, and manifested stronger tumorigenicity in vivo. The fabricated 3d OA-COL droplets reproduced a variety of TME parameters, constructed an in vitro model similar to the TME in vivo, and it may facilitate many investigations in cell biology and tumor biology.


Assuntos
Alginatos , Microambiente Tumoral , Alginatos/metabolismo , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fígado/metabolismo , Suínos
8.
Anim Nutr ; 8(1): 102-113, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34977380

RESUMO

In this study, we conducted a 56-d feeding trial to investigate the effects of replacing the fish oil (FO) with palm oil (PO) on the performance, tissue fatty acid (FA) composition, and mRNA levels of genes related to hepatic lipid metabolism in grouper (Epinephelus coioides). Five isolipidic (13% crude lipid) and isonitrogenous (48% CP) diets were formulated by incrementally adding PO to the control diet (25% fish meal and 9% added FO) to replace FO in the control diets. Triplicate groups of 30 groupers (initial weight: 12.6 ± 0.1 g) were fed one of the diets twice daily, to apparent satiety. The replacement of FO with 50% PO revealed maximum growth without affecting the performance and whole-body proximate compositions, and replacing FO with 100% PO revealed a comparable (P > 0.05) growth with that of the control diet, suggesting PO as a suitable alternative to FO. The analysis of FA profiles in the dorsal muscle and liver though reflected the FA profile of the diet, PO substitutions above 50% could compromise (P < 0.05) the FA profile in the liver and flesh of the fish species in comparison with the control diet. Furthermore, the mRNA levels of FAS, G6PD, LPL, PPARΑ, and Δ6FAD genes in the liver had positive linear and/or quadratic responses, but the SCD, HSL, ATGL, FABP, SREBP-1C and ELOVL5 had the opposite trend, with increasing dietary PO inclusion levels, whereas the mRNA level of ACC was not affected by dietary treatments. The optimal level of PO substitution for FO was estimated to be 47.1% of the feed, based on the regression analysis of percent weight gains against dietary PO inclusion levels; however, it might affect the FA profile in the liver and flesh of the fish species, and further study is required to investigate whether the changes in tissue FA composition will affect the welfare and market value over a production cycle of grouper.

9.
J Nanobiotechnology ; 19(1): 432, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930301

RESUMO

BACKGROUND: Distant metastasis to vital organs is the major contributor to breast cancer mortality, and regional lymph node metastasis is an important facilitator of distant metastasis and recurrence in this cancer. The early diagnosis and precise treatment of lymph node metastasis are crucial for staging and prognosis in breast cancer. Herein, we report a visualized precision medicine nanoplatform of metastatic lymph nodes for ultrasonic/photoacoustic (US/PA) dual modal imaging-guided in situ targeted hyperthermia-combined chemotherapy. RESULTS: Carbon nanoparticles (CNs), approved by the China Food and Drug Administration, were loaded with docetaxel and rationally combined with anti-hypoxia-inducible factor 1α antibody-modified poly (lactic-co-glycolic acid) (PLGA) nanoparticles to achieve the combination of passive targeting at the lymph nodes and intracellular targeting at HIF 1α factor. The accumulation and retention of nanoparticles in metastatic lymph nodes via lymphatic delivery were enhanced. Docetaxel could be effectively offloaded by CNs that have active carbon nanoparticles, and the PLGA membrane prevented drug leakage. The nanoparticles exhibited excellent photothermal performance with a photothermal conversion efficiency of 28.9%, killing tumor cells in metastatic lymph nodes through hyperthermia. In vitro and in vivo systematic evaluations revealed that hyperpyrexia triggered the rupture of nanoparticles caused by the phase transition of perfluorohexane, resulting in docetaxel release for achieving in situ hyperthermia-combined chemotherapy. CONCLUSIONS: The laser-triggered highly efficient in situ chemotherapy nanosystem achieves targeted synergistic chemo-hyperthermia treatment of metastatic lymph nodes, and lymphatic delivery represents a strategy to avoid additional injury caused by drugs entering the blood circulation.


Assuntos
Antineoplásicos/uso terapêutico , Hipertermia Induzida/métodos , Linfonodos/metabolismo , Nanopartículas/química , Neoplasias/tratamento farmacológico , Animais , Anticorpos/química , Anticorpos/imunologia , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carbono/química , Linhagem Celular Tumoral , Docetaxel/química , Docetaxel/metabolismo , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Raios Infravermelhos , Metástase Linfática , Nanomedicina , Nanopartículas/metabolismo , Neoplasias/patologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Transplante Heterólogo
10.
Front Endocrinol (Lausanne) ; 12: 789310, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35154002

RESUMO

Objectives: To screen out the predictors of central cervical lymph node metastasis (CLNM) for papillary thyroid carcinoma (PTC) and establish a prediction model to guide the operation of PTC patients (cN0). Methods: Data from 296 PTC patients (cN0) who underwent thyroid operation at the Second Affiliated Hospital of Chongqing Medical University were collected and retrospectively analyzed. They were divided into two groups in accordance with central CLNM or not. Their information, including ultrasound (US) features, BRAFV600E status, and other characteristics of the two groups, was analyzed and compared using univariate and multivariate logistic regression analyses, and the independent predictors were selected to construct a nomogram. The calibration plot, C-index, and decision curve analysis were used to assess the prediction model's calibration, discrimination, and clinical usefulness. Results: A total of 37.8% (112/296) of PTC patients had central CLNM, and 62.2% (184/296) did not. The two groups were compared using a univariate logistic regression analysis, and there were no significant differences between the two groups in sex, aspect ratio, boundary, morphology, hypoechoic nodule, thyroid peroxidase antibody, or tumor location (P>0.05), and there were significant differences between age, tumor size, capsule contact, microcalcifications, blood flow signal, thyroglobulin antibodies (TgAb), and BRAF gene status (P<0.05). A multivariate logistic regression analysis was performed to further clarify the correlation of these indices. However, only tumor size (OR=2.814, 95% Cl=1.634~4.848, P<0.001), microcalcifications (OR=2.839, 95% Cl=1,684~4.787, P<0.001) and TgAb (OR=1.964, 95% Cl=1.039~3,711, P=0.038) were independent predictors of central CLNM and were incorporated and used to construct the prediction nomogram. The model had good discrimination with a C-index of 0.715. An ROC curve analysis was performed to evaluate the accuracy of this model. The decision curve analysis showed that the model was clinically useful when intervention was decided in the threshold range of 16% to 80%. Conclusion: In conclusion, three independent predictors of central CLNM, including tumor size (> 1.0 cm), US features (microcalcifications), and TgAb (positive), were screened out. A visualized nomogram model was established based on the three predictors in this study, which could be used as a basis of central cervical lymph node dissection (CLND) for PTC patients (cN0).


Assuntos
Linfonodos/patologia , Câncer Papilífero da Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Autoanticorpos/imunologia , Calcinose/diagnóstico por imagem , Regras de Decisão Clínica , Feminino , Humanos , Metástase Linfática , Masculino , Pescoço , Esvaziamento Cervical , Nomogramas , Proteínas Proto-Oncogênicas B-raf/genética , Medição de Risco , Câncer Papilífero da Tireoide/diagnóstico por imagem , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/imunologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/imunologia , Carga Tumoral , Ultrassonografia
11.
ACS Omega ; 5(7): 3194-3206, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32118135

RESUMO

Breast cancer is one of the major diseases that threaten women's health. Lymph node (LN) metastasis is the most common metastatic path of breast cancer. Finding a simple, effective, and safe strategy to eliminate metastatic tumors in LNs is highly desired for clinical use. Carbon nanoparticles (CNs), as an LN tracer, have been widely used in the clinical setting. In addition, previous experiments have confirmed that CNs have good photoacoustic imaging and photothermal effects. In this study, we used CNs as a photothermal conversion material and drug carrier, poly(lactic-co-glycolic acid) (PLGA) as a film-forming material, and docetaxel as a chemotherapy drug to prepare multifunctional nanoparticles (DOC-CNPs). The prepared DOC-CNPs present as a black solution, which shows smooth spherical particles under light microscopy and transmission electron microscopy (TEM), and they have a good ability for liquid-gas phase transition, good dispersibility, high drug-loading capacity, and low cytotoxicity. In vitro, they can release drugs and inhibit tumor cells after laser irradiation. The photoacoustic (PA) signal intensity and the photothermal conversion efficiency increased with an increase in the concentration of DOC-CNPs. In vivo, after administration, the DOC-CNPs reached the LNs. After laser irradiation, the DOC-CNPs absorbed laser energy, and the temperature of the LNs increased high enough to achieve photothermal therapy under PA and ultrasound monitoring. Fracture of the DOC-CNPs was caused by the liquid-gas phase transition with the increased temperature, and the ruptured DOC-CNPs released docetaxel to achieve targeted chemotherapy. These findings suggested that DOC-CNPs can achieve precise treatment for metastatic LNs of breast cancer with PA and ultrasound visualization.

12.
Oncol Lett ; 18(3): 2995-3002, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452778

RESUMO

The aim of the present study was to evaluate the associations between the B-Raf proto-oncogene serine/threonine kinase (BRAF)V600E mutation and conventional and contrast-enhanced ultrasonographic features in patients with papillary thyroid carcinoma (PTC), and to subsequently investigate the clinical value of these associations. In total, 207 thyroid nodules (diameter ≤2 cm) were selected. Conventional ultrasound, contrast-enhanced ultrasound, BRAFV600E mutational analysis and ultrasound-guided fine-needle aspiration biopsy were preoperatively performed, and histopathological assessment of PTC was postoperatively confirmed. The nodules were divided into 2 groups based on the BRAFV600E mutational analysis, namely the mutant or the wild-type variant groups, and the association analyses of the ultrasonographic features between these 2 groups were performed. Overall, 74.9% (155/207) of the PTC nodules had the BRAFV600E mutation, while 25.1% (52/207) had the wild-type BRAF allele. The 2 groups were analyzed using univariate logistic regression analysis, which demonstrated no significant differences regarding morphology, boundary, hypoechogenicity of the nodules, blood flow signal, enhancement uniformity, enhancement degree and clearance time (P>0.05). Moreover, the 2 groups demonstrated significant differences regarding the aspect ratio, microcalcification, nodule size following enhancement, enhancement mode and enhancement time (P<0.05). A multivariate logistic regression analysis was performed to further validate the association of these features with the BRAFV600E mutation; however, only microcalcification [odds ratio (OR), 2.256; 95% confidence interval (CI), 1.160-5.500; P=0.020] and nodule size following enhancement (OR, 2.119; 95% CI, 1.039-4.321; P=0.039) were associated with the BRAF mutational status. The associations found between the two ultrasonographic features and BRAFV600E mutation indicate that they can predict the BRAF mutational status to provide a reliable basis for clinical diagnosis and treatment.

13.
Artigo em Inglês | MEDLINE | ID: mdl-28257076

RESUMO

Based on the panel data of 306 cities in China from 2002 to 2012, this paper investigates China's road transport fuel (i.e., gasoline and diesel) demand system by using the Almost Ideal Demand System (AIDS) and the Quadratic AIDS (QUAIDS) models. The results indicate that own-priceelasticitiesfordifferentvehiclecategoriesrangefrom-1.215to-0.459(byAIDS)andfrom -1.399 to-0.369 (by QUAIDS). Then, this study estimates the air pollution emissions (CO, NOx and PM2.5) and public health damages from the road transport sector under different oil price shocks. Compared to the base year 2012, results show that a fuel price rise of 30% can avoid 1,147,270 tonnes of pollution emissions; besides, premature deaths and economic losses decrease by 16,149 cases and 13,817.953 million RMB yuan respectively; while based on the non-linear health effect model, the premature deaths and total economic losses decrease by 15,534 and 13,291.4 million RMB yuan respectively. Our study combines the fuel demand and health evaluation models and is the first attempt to address how oil price changes influence public health through the fuel demand system in China. Given its serious air pollution emission and substantial health damages, this paper provides important insights for policy makers in terms of persistent increasing in fuel consumption and the associated health and economic losses.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Comércio , Modelos Teóricos , Petróleo/economia , Meios de Transporte/economia , Emissões de Veículos/análise , Poluição do Ar/prevenção & controle , China , Cidades , Humanos , Saúde Pública , Incerteza
14.
Anal Chem ; 86(24): 12229-35, 2014 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25393607

RESUMO

Fluorescent aptamer probes physisorbed on graphene oxide (GO) have recently emerged as a useful sensing platform. A signal is generated by analyte-induced probe desorption. To address nonspecific probe displacement and the false positive signal, we herein report a covalently linked aptamer probe for adenosine triphosphate (ATP) detection. A fluorophore and amino dual modified aptamer was linked to the carboxyl group on GO with a coupling efficiency of ∼50%. The linearity, specificity, stability, and regeneration of the covalent sensor were systematically studied and compared to the physisorbed probe. Both sensors have similar sensitivity, but the covalent one is more resistant to nonspecific probe displacement by proteins. The covalent sensor has a dynamic range from 0.125 to 2 mM ATP in buffer at room temperature and is resistance to DNase I. Intracellular ATP imaging was demonstrated using the covalent sensor, which generated a higher fluorescence signal than the physisorbed sensor. After the cells were stimulated with 5 mM Ca(2+) for ATP production, the intracellular signal enhanced by 31.8%. This work highlights the advantages of covalent aptamer sensors using GO as both a quencher and a delivery vehicle for intracellular metabolite detection.


Assuntos
Trifosfato de Adenosina/análise , Aptâmeros de Nucleotídeos/química , Grafite/química , Sondas Moleculares , Óxidos/química , Sequência de Bases
15.
Endocrine ; 43(3): 714-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23008094

RESUMO

The roles of uncoupling protein-2 (UCP2) on the androgen synthesis of granulosa cells derived from patients with polycystic ovary syndrome (PCOS) and normal subjects were explored. Primary human granulosa cells from 18 patients who received in vitro fertilization (IVF) were examined; nine patients had PCOS with hyperandrogenism. Primary cultures were treated with genipin, a proton leak inhibitor, guanosine diphosphate (GDP), an UCP inhibitor, and triiodothyronine (T3), an inducer of UCP gene expression. Mitochondrial membrane potential was determined using the JC-1 assay. T3 induced P450scc and UCP2 expressions and testosterone synthesis in both normal and PCOS granulosa cells. Their expressions in response to T3 treatments were correlated in the PCOS group. Differences in testosterone synthesis were observed between normal and PCOS cells in response to genipin. Increased mitochondrial membrane potential was observed in response to genipin and GDP; while T3 decreased it. Increased ovarian UCP2 expression in response to T3 treatment in PCOS may alter pregnenolone synthesis by influencing P450scc expression, thus altering testosterone production. Further in vivo studies are necessary to fully elucidate the role of UCP2 in the hyperandrogenism commonly observed in PCOS.


Assuntos
Células da Granulosa/metabolismo , Hiperandrogenismo/metabolismo , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Síndrome do Ovário Policístico/metabolismo , Testosterona/biossíntese , Adulto , Aromatase/genética , Aromatase/metabolismo , Células Cultivadas , Feminino , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/patologia , Guanosina Difosfato/farmacologia , Humanos , Hiperandrogenismo/genética , Hiperandrogenismo/patologia , Canais Iônicos/genética , Iridoides/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Mitocondriais/genética , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , Tri-Iodotironina/farmacologia , Proteína Desacopladora 2
16.
Reprod Fertil Dev ; 23(4): 520-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21557918

RESUMO

Polycystic ovary syndrome (PCOS) may result from hypersensitivity to insulin, which is negatively regulated by uncoupling protein (UCP)-2. Because cholesterol side-chain cleavage enzyme (CYP11A1) is closely linked to PCOS, the expression of UCP-2 and CYP11A1 in ovarian tissues from PCOS patients was examined in the present study. Twelve PCOS patients with hyperandrogenaemia who underwent laparoscopic ovarian wedge resection and 12 age-matched control patients who underwent contralateral ovarian biopsy were enrolled in the study. UCP-2 expression in early stage (primordial, primary and secondary) and late stage (sinus and mature) follicles was examined using immunohistochemistry, whereas UCP-2 and CYP11A1 mRNA and protein levels in ovarian tissue were determined using quantitative reverse transcription-polymerase chain reaction and western blot analyses, respectively. UCP-2 expression increased significantly with follicular development in both control and PCOS tissue, with expression in early stage follicles from PCOS patients significantly greater than that in controls. In addition, both UCP-2 and CYP11A1mRNA and protein levels, mean fasting blood glucose concentrations and fasting serum insulin levels were significantly higher in PCOS patients compared with the control group. Finally, a significant correlation between UCP-2 and CYP11A1 expression was found in PCOS but not control patients. In conclusion, in PCOS patients, there was a correlation between UCP-2 and CYP11A1 expression, which was significantly higher than in the control group. These changes in UCP-2 and CYP11A1 expression may mediate follicle development in PCOS.


Assuntos
Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Canais Iônicos/genética , Proteínas Mitocondriais/genética , Síndrome do Ovário Policístico/genética , Adulto , Estudos de Casos e Controles , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Feminino , Regulação da Expressão Gênica , Células da Granulosa/metabolismo , Células da Granulosa/patologia , Humanos , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Ovário/metabolismo , Ovário/patologia , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Proteína Desacopladora 2 , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA