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1.
Int. j. morphol ; 42(1): 154-161, feb. 2024. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1528830

RESUMO

SUMMARY: Esophageal cancer is one of the most aggressive gastrointestinal cancers. Invasion and metastasis are the main causes of poor prognosis of esophageal cancer. SPRY2 has been reported to exert promoting effects in human cancers, which controls signal pathways including PI3K/AKT and MAPKs. However, the expression of SPRY2 in esophageal squamous cell carcinoma (ESCC) and its underlying mechanism remain unclear. In the present study, we aimed to investigate the detailed role of SPRY2 in the regulation of cell proliferation, invasion and ERK/AKT signaling pathway in ESCC. It was identified that the expression level of SPRY2 in ESCC was remarkably decreased compared with normal tissues, and it was related to clinicopathologic features and prognosis ESCC patients. The upregulation of SPRY2 expression notably inhibited the proliferation, migration and invasion of Eca-109 cells. In addition, the activity of ERK /AKT signaling was also suppressed by the SPRY2 upregulation in Eca-109 cells. Our study suggests that overexpression of SPRY2 suppress cancer cell proliferation and invasion of by through suppression of the ERK/AKT signaling pathways in ESCC. Therefore, SPRY2 may be a promising prognostic marker and therapeutic target for ESCC.


El cáncer de esófago es uno de los cánceres gastrointestinales más agresivos. La invasión y la metástasis son las principales causas de mal pronóstico del cáncer de esófago. Se ha informado que SPRY2 ejerce efectos promotores en los cánceres humanos, que controla las vías de señales, incluidas PI3K/AKT y MAPK. Sin embargo, la expresión de SPRY2 en el carcinoma de células escamosas de esófago (ESCC) y su mecanismo subyacente aún no están claros. En el presente estudio, nuestro objetivo fue investigar el papel detallado de SPRY2 en la regulación de la proliferación celular, la invasión y la vía de señalización ERK/AKT en ESCC. Se identificó que el nivel de expresión de SPRY2 en ESCC estaba notablemente disminuido en comparación con los tejidos normales, y estaba relacionado con las características clínico-patológicas y el pronóstico de los pacientes con ESCC. La regulación positiva de la expresión de SPRY2 inhibió notablemente la proliferación, migración e invasión de células Eca-109. Además, la actividad de la señalización de ERK/AKT también fue suprimida por la regulación positiva de SPRY2 en las células Eca-109. Nuestro estudio sugiere que la sobreexpresión de SPRY2 suprime la proliferación y la invasión de células cancerosas mediante la supresión de las vías de señalización ERK/AKT en ESCC. Por lo tanto, SPRY2 puede ser un marcador de pronóstico prometedor y un objetivo terapéutico para la ESCC.


Assuntos
Humanos , Neoplasias Esofágicas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Proteínas de Membrana/metabolismo , Imuno-Histoquímica , Biomarcadores Tumorais , Western Blotting , MAP Quinases Reguladas por Sinal Extracelular , Proliferação de Células , Proteínas Proto-Oncogênicas c-akt
2.
Int J Occup Saf Ergon ; 30(1): 168-184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963818

RESUMO

Objectives This study aimed to provide greater insight into the characteristics of severe and extraordinarily severe gas explosion accidents (SESGEAs). Methods. The study analyzed the accident characteristics and causes of SESGEAs. As an example, we conducted a specialized case analysis using the 24Model (fourth edition) on the recent Baoma coal mine gas explosion. Results. SESGEA data are characterized by greater volatility, with significant differences in the geographical distribution, temporal distribution and attributed characteristics of the accidents. From the accident analysis: chaotic ventilation management was the most serious accident cause of SESGEAs; unsafe acts related to ventilation operations accounted for 18.51% of all unsafe acts; coal miners lack professional safety knowledge and have a serious fluke mentality in mining work; enterprises have insufficient enforcement of safety procedure documents, and lack of attention to the allocation of underground human resources and safety training systems; and the importance of safety, the role of the safety department and satisfaction with safety facilities have become the most serious missing items of safety culture. Conclusion. This study can provide important data support and management basis to assist mine operators in developing more targeted accident prevention strategies.


Assuntos
Minas de Carvão , Explosões , Humanos , Acidentes de Trabalho/prevenção & controle , China/epidemiologia , Carvão Mineral , Acidentes
3.
Opt Lett ; 45(6): 1391-1394, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32163973

RESUMO

Due to the unique properties of terahertz (THz) waves, THz phase imaging has been widely investigated to retrieve the absorption and phase modulation of dielectric two-dimensional thin samples, as well as multiple stacked samples. In this Letter, we apply the three-dimensional ptychographic iterative engine algorithm for continuous-wave THz full-field multi-layered phase imaging. The complex-valued transmission function of two-layered polypropylene thin plates and the corresponding probe function are reconstructed, respectively, which are immune to crosstalk of different layers. The phenomenon of the field-of-view enlargement at the second object layer is observed. This lensless compact imaging method can be potentially used for THz three-dimensional imaging.

4.
Adv Healthc Mater ; 7(17): e1800485, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29995353

RESUMO

An insufficient drug concentration at the target site and drug efflux resulting in poor efficacy is recognized as important obstacles in tumor treatment. Herein, novel lipid nanoparticles (LNPs) with redox-responsive properties based on disulfide bond-contained, quercetin (Qu)-grafted glyceryl caprylate-caprate (Gcc) are introduced (Qu-SS-Gcc LNPs). Qu-SS-Gcc LNPs show good entrapment of paclitaxel (PTX) due to π-π stacking between the aromatic rings of Qu and PTX. In vitro experiments indicate that Qu-SS-Gcc LNPs can selectively respond to high levels of reducing substances by breakdown of disulfide bonds, thus achieving rapid and efficient drug release, and only dissociate rapidly in tumor cells rather than in normal cells. Meanwhile, the Qu released concomitantly with the breakdown of disulfide bonds combines with P-gp and inhibits the drug efflux triggered by P-gp. Using an orthotopic 4T1 mouse mammary tumor model in BALB/c mice, PTX/Qu-SS-Gcc LNPs exhibit superior antitumor efficacy compared to Taxol, in addition better biosafety and inhibition of chemotherapy-triggered P-gp overexpression are achieved. Taken together, this work designs and implements redox-responsive drug release and drug efflux inhibition in tumor cells via modified LNPs, which not only leads to efficient drug release but also solves the problem of drug efflux that exists in stimulus-responsive systems.


Assuntos
Antineoplásicos Fitogênicos/química , Nanopartículas/química , Paclitaxel/química , Animais , Antineoplásicos Fitogênicos/farmacocinética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Oxirredução , Paclitaxel/farmacocinética , Paclitaxel/farmacologia
5.
Int J Pharm ; 547(1-2): 72-82, 2018 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-29803792

RESUMO

This study was undertaken to generate a novel dual targeting fusion protein (DTF), targeting tumor necrosis factor α (TNF-α) and interleukin 17A (IL-17A), and determine its anti-arthritis properties in vitro and in vivo. DTF consisted of an anti-IL-17A single chain variable fragment, a soluble TNF receptor 1, and an Fc fragment. Both clinical and histopathological evaluations suggest that DTF and etanercept can ameliorate collagen induced arthritis. However, the arthritis severity score of DTF-treated mice was lower than that of etanercept-treated mice. In addition, DTF was more potent than etanercept in decreasing the ratio of RANKL/OPG in the serum and rebalancing the population ratio of Treg/Th17 cells in the spleens. In vitro, IL-17A and TNF-α had synergistic effects in inducing the expression of inflammatory cytokines in fibroblast-like synoviocyte from RA patients (RA-FLS), human leukemia (THP-1), and rheumatoid synovial fibroblast (MH7A). IL-17A and TNF-α also had synergistic effects in inducing proliferation and migration of MH7A cells. However, we observed that DTF was more efficient than etanercept in suppressing these synergistic effects. Our results demonstrate that DTF is highly efficient in the treatment of arthritis and has the potential to overcome the limited therapeutic responses obtained with single cytokine neutralization.


Assuntos
Artrite Experimental/tratamento farmacológico , Citocinas/imunologia , Fragmentos Fc das Imunoglobulinas/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/imunologia , Células CHO , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cricetulus , Etanercepte/uso terapêutico , Feminino , Humanos , Articulações/efeitos dos fármacos , Articulações/patologia , Camundongos Endogâmicos C57BL , Osteoprotegerina/imunologia , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia
6.
Adv Mater ; 30(14): e1706407, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29484719

RESUMO

Insufficient drug release as well as poor drug penetration are major obstacles for effective nanoparticles (NPs)-based cancer therapy. Herein, the high aqueous instability of amorphous calcium carbonate (ACC) is employed to construct doxorubicin (DOX) preloaded and monostearin (MS) coated "Pandora's box" (MS/ACC-DOX) NPs for lipase-triggered water-responsive drug release in lipase-overexpressed tumor tissue to induce a neighboring effect and enhance drug penetration. MS as a solid lipid can prevent potential drug leakage of ACC-DOX NPs during the circulatory process, while it can be readily be disintegrated in lipase-overexpressed SKOV3 cells to expose the ACC-DOX core. The high aqueous instability of ACC will lead to burst release of the encapsulated DOX to induce apoptosis and cytotoxicity to kill the tumor cells. The liberated NPs from the dead or dying cells continue to respond to the ubiquitous aqueous environment to sufficiently release DOX once unpacked, like the "Pandora's box", leading to severe cytotoxicity to neighboring cells (neighboring effect). Moreover, the continuously released free DOX molecules can readily diffused through the tumor extracellular matrix to enhance drug penetration to deep tumor tissue. Both effects contribute to achieve elevated antitumor benefits.


Assuntos
Lipase/química , Linhagem Celular Tumoral , Doxorrubicina , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Humanos , Nanopartículas , Neoplasias , Água
7.
Int Immunopharmacol ; 56: 301-309, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29414665

RESUMO

Type 2 diabetes mellitus (T2DM) is accompanied by abnormal glucose metabolism and low-grade chronic inflammation. Fibroblast growth factor 21 (FGF-21) is a novel metabolic regulator and can function as an endocrine hormone to regulate glucose and lipid metabolism. Recently, FGF-21 was found to have anti-inflammatory effect, to our knowledge, the effect of FGF-21 on inflammatory state in diabetes has not been elucidated. Here, we use db/db mice as a Type 2 diabetes model to determine whether FGF-21 alleviates inflammatory state while improves hyperglycemia. Our results demonstrated that FGF-21 not only showed potent long lasting hypoglycemic effect, but also demonstrated strong anti-inflammatory effect in the serum and white adipose tissue. Besides, in vitro experiments, insulin resistance (IR) was induced in 3T3-L1 adipocytes by treating with TNF-α. Our results showed that TNF-α impaired glucose metabolism of 3T3-L1 adipocytes but FGF-21 repressed gene expression of inflammatory factors caused by IR and consequently improved the glucose metabolism in 3T3-L1 adipocytes. Furthermore, FGF-21 ameliorated glucose uptake of TNF-α-induced IR in 3T3-L1 adipocytes by inhibiting NF-κB signaling pathway.


Assuntos
Adipócitos/fisiologia , Tecido Adiposo Branco/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Glucose/metabolismo , Inflamação/metabolismo , Animais , Linhagem Celular , Hiperglicemia , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , NF-kappa B/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo
8.
Sci Rep ; 5: 8445, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25676705

RESUMO

Terahertz waves provide a better contrast in imaging soft biomedical tissues than X-rays, and unlike X-rays, they cause no ionisation damage, making them a good option for biomedical imaging. Terahertz absorption imaging has conventionally been used for cancer diagnosis. However, the absorption properties of a cancerous sample are influenced by two opposing factors: an increase in absorption due to a higher degree of hydration and a decrease in absorption due to structural changes. It is therefore difficult to diagnose cancer from an absorption image. Phase imaging can thus be critical for diagnostics. We demonstrate imaging of the absorption and phase-shift distributions of 3.2 mm × 2.3 mm × 30-µm-thick human hepatocellular carcinoma tissue by continuous-wave terahertz digital in-line holography. The acquisition time of a few seconds for a single in-line hologram is much shorter than that of other terahertz diagnostic techniques, and future detectors will allow acquisition of meaningful holograms without sample dehydration. The resolution of the reconstructions was enhanced by sub-pixel shifting and extrapolation. Another advantage of this technique is its relaxed minimal sample size limitation. The fibrosis indicated in the phase distribution demonstrates the potential of terahertz holographic imaging to obtain a more objective, early diagnosis of cancer.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Holografia , Neoplasias Hepáticas/diagnóstico , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Camundongos , Radiografia , Imagem Terahertz
9.
Fish Physiol Biochem ; 39(3): 459-69, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22955963

RESUMO

Chemokines are small, secreted cytokine peptides known principally for their ability to induce migration and activation of leukocyte populations and regulate the immune response mechanisms. The cobia (Rachycentron canadum), a marine finfish species, has a great potential for net cage aquaculture in the South China Sea. We isolated and characterized a CC chemokine cDNA from cobia-designated RcCC2. Its cDNA is 783 bp in length and encodes a putative protein of 110 amino acids. Homology and phylogenetic analysis revealed that the RcCC2 gene, which contains four conserved cysteine residues, shares a high degree of similarity with other known CC chemokine sequences and is closest to the CCL19/21 clade. The mRNA of RcCC2 is expressed constitutively in all tested tissues, including gill, liver, muscle, spleen, kidney, head kidney, skin, brain, stomach, intestine and heart, but not blood, with the highest level of expression in gill and liver. The reverse transcription quantitative polymerase chain reaction was used to examine the expression of the RcCC2 gene in immune-related tissues, including head kidney, spleen and liver, following intraperitoneal injection of the viral mimic polyriboinosinic polyribocytidylic acid, formalin-killed Vibrio carchariae (bacterial vaccine) and phosphate-buffered saline as a control. RcCC2 gene expression was up-regulated differentially in head kidney, spleen and liver during 12 h after challenge. These results indicate that the RcCC2 gene is inducible and is involved in immune responses, suggesting RcCC2 has an important role in the early stage of viral and bacterial infections.


Assuntos
Quimiocinas CC/genética , Quimiocinas CC/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Perciformes/genética , Animais , Vacinas Bacterianas/farmacologia , Sequência de Bases , Clonagem Molecular , Análise por Conglomerados , Primers do DNA/genética , DNA Complementar/genética , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Filogenia , Polinucleotídeos/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Especificidade da Espécie
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