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1.
Cancer Cell Int ; 19: 295, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807117

RESUMO

The potent pleiotropic lipid mediator sphingosine-1-phosphate (S1P) participates in numerous cellular processes, including angiogenesis and cell survival, proliferation, and migration. It is formed by one of two sphingosine kinases (SphKs), SphK1 and SphK2. These enzymes largely exert their various biological and pathophysiological actions through one of five G protein-coupled receptors (S1PR1-5), with receptor activation setting in motion various signaling cascades. Considerable evidence has been accumulated on S1P signaling and its pathogenic roles in diseases, as well as on novel modulators of S1P signaling, such as SphK inhibitors and S1P agonists and antagonists. S1P and ceramide, composed of sphingosine and a fatty acid, are reciprocal cell fate regulators, and S1P signaling plays essential roles in several diseases, including inflammation, cancer, and autoimmune disorders. Thus, targeting of S1P signaling may be one way to block the pathogenesis and may be a therapeutic target in these conditions. Increasingly strong evidence indicates a role for the S1P signaling pathway in the progression of cancer and its effects. In the present review, we discuss recent progress in our understanding of S1P and its related proteins in cancer progression. Also described is the therapeutic potential of S1P receptors and their downstream signaling cascades as targets for cancer treatment.

2.
J Vasc Interv Radiol ; 30(12): 2026-2035.e2, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31590966

RESUMO

PURPOSE: To evaluate the effect of transarterial infusion of iRGD-modified and doxorubicin-loaded zirconia-composite nanoparticles (R-DZCNs) with lipiodol in the improvement of the distribution of doxorubicin (DOX) in liver tumors and its antitumor efficacy. MATERIALS AND METHODS: The effect of R-DZCNs was evaluated in vitro by tumor cellular uptake and cytotoxicity assays. For the in vivo study, DOX distribution and antitumor efficiency were assessed. In the DOX distribution study, VX2 tumor-bearing rabbits received transarterial infusion of lipiodol with DOX, doxorubicin-loaded zirconia-composite nanoparticles (DZCNs), or R-DZCNs, respectively. DOX distribution was assessed by immunofluorescence. In the antitumor study, tumor-bearing rabbits received transarterial infusions of lipiodol with DOX, DZCNs, R-DZCNs, or saline respectively. Tumor volume was measured using magnetic resonance imaging, and the expression of apoptosis-related factors (caspase-3, Bax, Bcl-2) was analyzed by immunohistochemistry and Western blotting. RESULTS: R-DZCNs increased cellular uptake and caused stronger cytotoxicity. Compared with the DOX + lipiodol or DZCNs + lipiodol group, the R-DZCNs + lipiodol group showed more DOX fluorescence spots (2,449.15 ± 444.14 vs. 3,464.73 ± 632.75 or 5,062.25 ± 585.62, respectively; P < .001) and longer penetration distance (117.58 ± 19.36 vs 52.64 ± 8.53 or 83.37 ± 13.76 µm, respectively; P < .001). In the antitumor study, the R-DZCNs + lipiodol group showed smaller tumor volumes than the DOX + lipiodol or DZCNs + lipiodol group (1,223.87 ± 223.58 vs. 3,695.26 ± 666.25 or 2281.06 ± 457.21 mm3, respectively; P = .005).The greatest extent of tumor cell apoptosis was observed in R-DZCNs + lipiodol group immunohistochemistry and Western blotting results. CONCLUSIONS: Transarterial infusion of R-DZCNs with lipiodol improved the distribution of DOX and enhanced its antitumor efficacy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Quimioembolização Terapêutica , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Óleo Etiodado/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Nanopartículas Metálicas , Oligopeptídeos/administração & dosagem , Zircônio/administração & dosagem , Animais , Antibióticos Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Células Hep G2 , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Imageamento por Ressonância Magnética , Masculino , Oligopeptídeos/metabolismo , Coelhos , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Zircônio/metabolismo
3.
J Vasc Surg ; 67(1): 300-308.e2, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28479097

RESUMO

OBJECTIVE: Animal models are required to explore the mechanisms of and therapy for proximal descending thoracic aortic aneurysm (TAA). This study aimed to establish a reproducible swine model of proximal descending TAA that can further explain the occurrence and progression of proximal descending TAA. METHODS: Eighteen Chinese Wuzhishan miniature pigs (30.32 ± 1.34 kg) were randomized into the elastase group (n = 12) and the control group (n = 6). The elastase group received intra-adventitial injections of elastase (5 mL, 20 mg/mL), and the control group received injections of physiologic saline solution. A 4-cm descending thoracic aortic segment proximal to the left subclavian artery was isolated. The distance between the left subclavian artery and the injection starting point of the descending thoracic aorta was 0.5 cm. Elastic protease was circumferentially injected intra-adventitially into the isolated segment of the aortic wall in the elastase group by a handmade bent syringe. The length of the elastic protease injection was 2 cm. An average of 12 injection points were distributed in this 2-cm aortic segment. Each injection point used about 0.4 mL of elastic protease. The distance between two injection points was about 1.5 cm. All animals underwent digital subtraction angiography preoperatively and 3 weeks after operation. Three weeks after TAA induction, aortas were harvested for biochemical and histologic measurements. RESULTS: All animals in the elastase group developed TAAs. No aneurysms were observed in the control group. The distance between the left subclavian artery and the TAA was 8.00 ± 4.19 mm. Preoperative and postoperative aortic diameters of the elastase group were 15.42 ± 0.43 mm and 24.53 ± 1.41 mm, respectively (P < .0001). Preoperative and postoperative aortic diameters of the control group were 15.31 ± 0.33 mm and 15.57 ± 0.40 mm, respectively (P = .5211). The changes of aortic structure and composition included reduction of smooth muscle cells and degradation of elastic fibers. Levels of matrix metalloproteinases 2 and 9 were increased in TAA tissue. CONCLUSIONS: This study established a reproducible large animal model of proximal descending TAA. This model has the same biochemical characteristics as human aneurysms in the aspects of aortic expansion, aortic middle-level degeneration, and changes in the levels of matrix metalloproteinases and provides a platform for further study.


Assuntos
Túnica Adventícia/efeitos dos fármacos , Aorta Torácica/efeitos dos fármacos , Aneurisma da Aorta Torácica/induzido quimicamente , Modelos Animais de Doenças , Elastase Pancreática/farmacologia , Porco Miniatura/fisiologia , Túnica Adventícia/patologia , Angiografia Digital , Animais , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/patologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/patologia , Progressão da Doença , Tecido Elástico/efeitos dos fármacos , Tecido Elástico/patologia , Humanos , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Distribuição Aleatória , Suínos/fisiologia , Porco Miniatura/anatomia & histologia
4.
Exp Mol Pathol ; 102(3): 492-499, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28506767

RESUMO

The ablation of Mig-6 has been shown to induce tumor formation in various tissues. However, the relationships between Mig-6 expression, clinical pathological factors, and prognosis have not been clarified in hepatocellular carcinoma (HCC), and the mechanism by which Mig-6 regulates the proliferation of HCC cells has not been reported. In this study, we investigated the clinical significance of the loss of Mig-6 expression in HCC and the mechanism underlying the inhibition of cell proliferation by Mig-6. The down-regulation of Mig-6 correlated significantly with large tumors, a more advanced BCLC stage, and a more advanced TNM stage, and low Mig-6 expression predicted significantly reduced survival. Low Mig-6 expression and high Cyclin D1 expression were independent predictors for survival. The overexpression of Mig-6 led to significant G1 arrest and growth inhibition in HCC cells, possibly through the inhibition P-ERK and Cyclin D1. These results indicate that Mig-6 expression is low in HCC, which predicts a poor prognosis. Mig-6 may regulate cell proliferation and the cell cycle through the P-ERK/Cyclin D1 pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Hepatocelular/diagnóstico , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/diagnóstico , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Regulação para Baixo , Feminino , Células Hep G2 , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , Transfecção , Proteínas Supressoras de Tumor/genética
5.
J Nanosci Nanotechnol ; 16(3): 2313-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27455635

RESUMO

Although mesoporous silica nanoparticles (MSNs) are widely used in food products, cosmetics and nanomedicines as vector for drug delivery, data on their potential genotoxocity are limited. The aim of this study was to investigate the cytotoxic and genotoxic potentials of MSNs of different shapes, and to establish a high-throughput screening method for nanoparticles. We used functional macrophage receptor with collagenous structure (MARCO)-expressing DNA repair deficient chicken DT40 cells, which are designed to internalize nanoparticles and to be deficient in several specific DNA repair pathways. In addition, we verified the validity of this assay by analyzing and characterizing the genotoxicity of sphere- or rod-shaped MSNs. We demonstrated that both sphere- and rod-shaped MSNs were cytotoxic, and that this effect was greater in FEN1(-/-) and REV3(-/-) cells compared with wild-type cells. Effects of rod-shaped MSNs were more severe compared with sphere-shaped MSNs. Furthermore, MSNs induced oxidative damage and a larger number of mitotic chromosomal aberrations in repair-deficient cells compared with repair-proficient cells. Taken together, this assay system using the chimeric receptor-expressing DNA repair-deficient DT40 cells provides a sensitive method to screen for genotoxicity of MSNs.


Assuntos
Nanopartículas , Dióxido de Silício/química , Dióxido de Silício/toxicidade , Animais , Linhagem Celular , Embrião de Galinha , Aberrações Cromossômicas , Reparo do DNA , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Testes de Mutagenicidade
6.
J Vasc Surg ; 62(4): 1054-63, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24726826

RESUMO

OBJECTIVE: This study tested the hypothesis that an experimental model of abdominal aortic aneurysm in rabbits results in progressive enlargement when induced by a combination of periaortic elastase administration and aortic coarctation. METHODS: Male New Zealand white rabbits were randomly divided into four groups: (A) stenosis (n = 12), (B) elastase (n = 12), (C) aneurysm (n = 15), and (D) control (n = 12). The stenosis group received an extrinsic coarctation below the right renal artery, the elastase group received a 10-minute administration of 60 µL elastase (1 U/µL) in a 1.5-cm aortic segment, the aneurysm group received stenosis and elastase, and a sham operation was performed in the control group. The aortic diameter was measured after 1, 2, 4, 8, and 16 weeks, and animals were subsequently euthanized for histopathologic and immunohistochemical studies. RESULTS: All animals in the aneurysm group developed aneurysm by 2 weeks after treatment, with average diameters of 5.21 ± 0.74 mm by 2 weeks, 6.23 ± 1.10 mm by 4 weeks, 7.87 ± 0.50 mm by 8 weeks, and 9.40 ± 0.36 mm by 16 weeks. Aortic diameter dilated progressively, and all aneurysms developed by 4 weeks in the stenosis group (4.17 ± 0.22 mm). Only one aneurysm was seen in the elastase group by week 1 (3.60 ± 0.64 mm), and no aneurysm formed in the control group by week 8 (2.47 ± 0.38 mm). The aneurysm group exhibited less media thickness, elastin content, and endothelial recovery, but stronger expression of matrix metalloproteinase 2 and 9 and rabbit macrophage compared with the control group. CONCLUSIONS: This novel rabbit abdominal aortic aneurysm model with a gradually enlarging diameter is simply and reliably induced, appropriately mimicking human aortic aneurysm disease.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Elastase Pancreática/administração & dosagem , Angiografia Digital , Animais , Aneurisma da Aorta Abdominal/induzido quimicamente , Coartação Aórtica/patologia , Colágeno/análise , Hemodinâmica , Imuno-Histoquímica , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Modelos Animais , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Coelhos
7.
Acta Cardiol Sin ; 31(5): 406-13, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27122900

RESUMO

BACKGROUND: The aim of this study was to evaluate the feasibility of a high fat diet (HFD) associated with pancreatic elastase (PE) infiltration, in establishing the rabbit aortic atherosclerosis model. METHODS: The HFD+PE method and the HFD+saccule injury (SI) method were simultaneously used to prepare the rabbit atherosclerosis model; the control group was established with the normal diet. Biochemical indicators, radiological imaging, pathomorphology and immunohistochemistry were used to evaluate the HFD+PE modeling results. RESULTS: There were significant changes in the blood lipid contents, as well as the pathomorphological and immunohistochemical results between the two experimental groups and the control group (p < 0.05). However, there was no difference between the two experimental groups. The rabbit aortic atherosclerosis model prepared by the HFD+PE method had no significant difference in the local vascular pathomorphological and immunohistochemical results with the traditional HFD+SI method. CONCLUSIONS: The use of HFD with PE infiltration is feasible in establishing the rabbit aortic atherosclerosis model. KEY WORDS: Animal model; Atherosclerosis; Rabbit.

8.
BMC Nephrol ; 15: 140, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25182068

RESUMO

BACKGROUND: To evaluate the effects of contrast agents containing increasing concentrations of iodine on the renal oxygenation level determined by blood oxygenation level dependent (BOLD) magnetic resonance imaging (MRI) in a rabbit model of diabetic nephropathy. METHODS: BOLD-MRI was performed using saline or iodinated (I) contrast agents (200, 240, 300, 350 and 400 mg I/mL) at 1, 24, 48, and 72 h after experimentally inducing type 2 diabetic nephropathy in rabbits. Differences in renal oxygenation levels between type 1 and type 2 diabetic nephropathy were also assessed by BOLD-MRI after injecting 400 mg I/mL of contrast agent. RESULTS: Contrast agents increased the R2* values of the renal cortex, outer medulla, and inner medulla to the maximum levels at 24 h. The R2* values then decreased to their lowest levels at 72 h. The R2* was highest following injection of 400 mg I/mL, especially in the outer medulla. The R2* values were not significantly different between types 1 and 2 diabetic nephropathy. CONCLUSIONS: Iodinated contrast agents had the greatest influence on renal outer medulla oxygenation level at 24 h in type 2 diabetic nephropathy, with the greatest effects observed at the 400 mg I/mL dose level. There were no differences in BOLD-MRI values between type 1 and type 2 diabetic nephropathy after administering the contrast agent at 400 mg I/mL.


Assuntos
Meios de Contraste , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Nefropatias Diabéticas/metabolismo , Imageamento por Ressonância Magnética/métodos , Consumo de Oxigênio/fisiologia , Animais , Meios de Contraste/administração & dosagem , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Nefropatias Diabéticas/diagnóstico , Relação Dose-Resposta a Droga , Radioisótopos do Iodo/administração & dosagem , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Coelhos
9.
J Pharm Anal ; 14(7): 100952, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39185337

RESUMO

Microwave thermotherapy (MWTT), as a treatment for tumors, lacks specificity and requires sensitizers. Most reported microwave sensitizers are single metal-organic frameworks (MOFs), which must be loaded with ionic liquids to enhance the performance in MWTT. Meanwhile, MWTT is rarely combined with other treatment modalities. Here, we synthesized a novel Fe-Cu bimetallic organic framework FeCuMOF (FCM) by applying a hydrothermal method and further modified it with methyl polyethylene glycol (mPEG). The obtained FCM@PEG (FCMP) showed remarkable heating performance under low-power microwave irradiation; it also acted as a novel nanospheres enzyme to catalyze H2O2 decomposition, producing abundant reactive oxygen species (ROS) to deplete glutathione (GSH) and prevent ROS clearance from tumor cells during chemodynamic treatment. The FCMP was biodegradable and demonstrated excellent biocompatibility, allowing it to be readily metabolized without causing toxic effects. Finally, it was shown to act as a suitable agent for T2 magnetic resonance imaging (MRI) in vitro and in vivo. This new bimetallic nanostructure could successfully realize two tumor treatment modalities (MWTT and chemodynamic therapy) and dual imaging modes (T2 MRI and microwave thermal imaging). Our findings represent a breakthrough for integrating the diagnosis and treatment of tumors and provides a reference for developing new microwave sensitizers.

10.
Acta Biomater ; 172: 382-394, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37797707

RESUMO

Microwave (MW) thermal therapy has been developed as an effective clinical strategy that can achieve pronounced antitumor activity and also has the potential to trigger antitumor immunity. However, patients generally face high rates of tumor recurrence following MW treatment, limiting the long-term benefits of such treatment. The combination of MW treatment and immunomodulatory strategies may represent a promising means of reprogramming the immunosuppressive tumor microenvironment (TME) in a manner conducive to lower recurrence rates. In this study, a Lenvatinib-loaded Gd/Fe metal-organic framework (Gd/FeMOF) was designed as a promising approach to enhancing such antitumor immunity. MW-enhanced dynamic Gd/FeMOF sensitization can facilitate high levels of reactive oxygen species production under MW irradiation, resulting in stronger immunogenic tumor cell death. In parallel, the Lenvatinib released from Gd/FeMOF preparations can serve as an immune adjuvant that suppresses programmed death ligand 1 (PD-L1) expression and drives the reprogramming of the immunosuppressive TME. The Gd and Fe present within this MOF preparation also imbue it with magnetic resonance imaging capabilities. Importantly, in vivo animal model experiments confirmed the ability of GdFeMOF treatment to significantly enhance antitumor immunity while protecting against recurrence. Accordingly, this study offers a foundation for promising strategies aimed at the integrated diagnosis and durable treatment of cancer. STATEMENT OF SIGNIFICANCE: High rates of tumor recurrence following MW thermal therapy limit the long-term benefits of such treatment. We found that the administration of Lenvatinib-loaded Gd/FeMOF nanoparticles significantly reduced tumor recurrence after MW thermal therapy. Under MW irradiation, the Gd/FeMOF nanoparticles were found to augment the immune response due to facilitation of the process of immunogenic cell death. In addition, the released Lenvatinib could act as an immune adjuvant to downregulate the expression of PD-L1 and reprogram the immunosuppressive state of the tumor microenvironment, thus further enhancing the immune response. This is significant because MW-induced immune responses are relatively weak and usually fail to effectively prevent tumor recurrence. The combination of MW treatment with an immunomodulatory strategy may solve this problem.


Assuntos
Antígeno B7-H1 , Neoplasias , Animais , Humanos , Micro-Ondas , Recidiva Local de Neoplasia , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Microambiente Tumoral
11.
Front Oncol ; 13: 992096, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814812

RESUMO

Background and objective: For patients with advanced colorectal liver metastases (CRLMs) receiving first-line anti-angiogenic therapy, an accurate, rapid and noninvasive indicator is urgently needed to predict its efficacy. In previous studies, dynamic radiomics predicted more accurately than conventional radiomics. Therefore, it is necessary to establish a dynamic radiomics efficacy prediction model for antiangiogenic therapy to provide more accurate guidance for clinical diagnosis and treatment decisions. Methods: In this study, we use dynamic radiomics feature extraction method that extracts static features using tomographic images of different sequences of the same patient and then quantifies them into new dynamic features for the prediction of treatmentefficacy. In this retrospective study, we collected 76 patients who were diagnosed with unresectable CRLM between June 2016 and June 2021 in the First Hospital of China Medical University. All patients received standard treatment regimen of bevacizumab combined with chemotherapy in the first-line treatment, and contrast-enhanced abdominal CT (CECT) scans were performed before treatment. Patients with multiple primary lesions as well as missing clinical or imaging information were excluded. Area Under Curve (AUC) and accuracy were used to evaluate model performance. Regions of interest (ROIs) were independently delineated by two radiologists to extract radiomics features. Three machine learning algorithms were used to construct two scores based on the best response and progression-free survival (PFS). Results: For the task that predict the best response patients will achieve after treatment, by using ROC curve analysis, it can be seen that the relative change rate (RCR) feature performed best among all features and best in linear discriminantanalysis (AUC: 0.945 and accuracy: 0.855). In terms of predicting PFS, the Kaplan-Meier plots suggested that the score constructed using the RCR features could significantly distinguish patients with good response from those with poor response (Two-sided P<0.0001 for survival analysis). Conclusions: This study demonstrates that the application of dynamic radiomics features can better predict the efficacy of CRLM patients receiving antiangiogenic therapy compared with conventional radiomics features. It allows patients to have a more accurate assessment of the effect of medical treatment before receiving treatment, and this assessment method is noninvasive, rapid, and less expensive. Dynamic radiomics model provides stronger guidance for the selection of treatment options and precision medicine.

12.
J Vasc Interv Radiol ; 23(11): 1529-36, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23101926

RESUMO

PURPOSE: The objective of this study was to determine the possibility of creating a novel animal model of abdominal aortic aneurysm (AAA) in rabbits by the periarterial application of papain. MATERIALS AND METHODS: Twelve New Zealand white rabbits were randomized into two groups: (1) the papain group, which received 2mg of papain (n = 8) and (2) the control group, which received physiologic saline solution (n = 4). A 1-cm aortic segment proximal to the bifurcation was isolated, and its adventitia was incubated with papain for 20 minutes. The rabbits underwent intravenous digital subtraction angiography (IVDSA) 5 and 21 days after the operation. The animals were then humanely killed for histomorphometric and immunohistochemical studies. RESULTS: All animals in the papain group developed AAA, with an average aneurysm diameter of 4.0 ± 0.6 and 4.1 ± 0.4 mm on days 5 and 21, respectively. No aneurysms were seen in the control group. On day 5, the papain-incubated aortas exhibited thinned and disorganized aortic walls, with decreased smooth muscle cells (SMCs) and fragmented and almost nonexistent elastic lamella. Media thickening, intimal hyperplasia, and smooth muscle cell regeneration were obvious on day 21. Immunostaining of matrix metalloproteinase (MMP)-9 and RAM11 showed strong expression in the papain group. On the contrary, the control group did not present histologic alterations and showed almost no expression of MMP-9 and RAM11. CONCLUSIONS: A novel in vivo rabbit model of AAA can be induced through periarterial application of papain for 20 minutes. This model is similar to an elastase-induced aneurysm model and could be useful to clarify AAA pathogenesis and endovascular treatment intervention.


Assuntos
Aorta Abdominal , Aneurisma da Aorta Abdominal/induzido quimicamente , Modelos Animais de Doenças , Papaína , Angiografia Digital , Animais , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/metabolismo , Biomarcadores/metabolismo , Imuno-Histoquímica , Metaloproteinase 9 da Matriz/metabolismo , Coelhos , Fatores de Tempo
13.
J Endovasc Ther ; 18(3): 407-15, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21679083

RESUMO

PURPOSE: To determine the efficacy of sirolimus-eluting bioabsorbable magnesium alloy stents (SEBMAS) in restenosis prevention. METHODS: A balloon-expandable bioabsorbable magnesium alloy stent (BMAS) was created and coated with biodegradable poly(lactic acid-co-trimethylene carbonate) that contained the antiproliferative drug sirolimus (140 ± 40 µg/cm²). Both the uncoated BMAS and the coated SEBMAS were deployed 2 cm apart in balloon-injured infrarenal abdominal aortas of 20 New Zealand white rabbits. The stented aortic segments were removed at 30, 60, 90, and 120 days (5 rabbits per interval) after implantation. The average stent strut sectional area of each group was measured to evaluate the degree of magnesium corrosion and to forecast the biodegradation time profile of the magnesium stent. Histology and histopathology of the sectioned stented aortic segments were performed to evaluate neointima formation, endothelialization, and inflammation. RESULTS: The SEBMAS degraded gradually after being implanted into the rabbit aorta, and total biocorrosion occurred after ~120 days. In all groups, the lumen area was significantly greater, but the neointimal area was significantly smaller in SEBMAS segments compared with the uncoated BMAS segments (p < 0.05) at all time points. There was no significant difference in the injury or inflammation scores between the groups. Endothelialization was delayed at 30 days in the SEBMAS segments vs. the uncoated BMAS segments. CONCLUSION: SEBMAS further reduces intimal hyperplasia and improves the lumen area when compared to uncoated BMAS; however, it delays vascular healing and endothelialization.


Assuntos
Ligas , Angioplastia/instrumentação , Aorta Abdominal/patologia , Doenças da Aorta/terapia , Arteriopatias Oclusivas/terapia , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Stents Farmacológicos , Magnésio , Sirolimo/administração & dosagem , Animais , Doenças da Aorta/etiologia , Doenças da Aorta/patologia , Arteriopatias Oclusivas/etiologia , Arteriopatias Oclusivas/patologia , Proliferação de Células , Constrição Patológica , Dioxanos , Modelos Animais de Doenças , Células Endoteliais/patologia , Hiperplasia , Ácido Láctico , Masculino , Poliésteres , Polímeros , Desenho de Prótese , Coelhos , Prevenção Secundária , Fatores de Tempo , Cicatrização
14.
Front Oncol ; 11: 809129, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35237502

RESUMO

INTRODUCTION: Pancreatic neuroendocrine neoplasms (PNENs) are rare pancreatic tumors originating from pancreatic neuroendocrine cells. There is no consensus on the treatment for PNENs with unresectable liver metastases. Transcatheter arterial chemoembolization (TACE) is the preferred treatment for unresectable primary liver cancer. But the efficacy of TACE and anticoagulation in PNENs with unresectable liver metastases and portal vein thrombosis has never been reported. METHODS AND RESULTS: We present the case of a 50-year-old male patient with hepatitis C who was found to have a single liver mass during a regular physical examination in 2016. The liver mass was surgically removed. Postoperative pathology suggested a neuroendocrine tumor of the liver, and it was suggested to look for the primary tumor. The patient was followed up until 2020, and the primary pancreatic tumor was found, along with multiple liver metastases and portal vein thrombosis. After transcatheter arterial embolization, anticoagulation, and endocrine therapy, the patient's tumor load was relieved, and the portal vein was recanalized. CONCLUSION: The article reports the disease course in a case of a functional pancreatic neuroendocrine tumor with liver metastasis and portal vein thrombosis and reviews previous literature. To our knowledge, we reported for the first time the efficacy of TACE and anticoagulation in PNENs with unresectable liver metastases and portal vein thrombosis.

15.
Bioact Mater ; 6(4): 916-927, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33210018

RESUMO

Copper is an indispensable trace metal element in the human body, which is mainly absorbed in the stomach and small intestine and excreted into the bile. Copper is an important component and catalytic agent of many enzymes and proteins in the body, so it can influence human health through multiple mechanisms. Based on the biological functions and benefits of copper, an increasing number of researchers in the field of biomaterials have focused on developing novel copper-containing biomaterials, which exhibit unique properties in protecting the cardiovascular system, promoting bone fracture healing, and exerting antibacterial effects. Copper can also be used in promoting incisional wounds healing, killing cancer cells, Positron Emission Tomography (PET) imaging, radioimmunological tracing and radiotherapy of cancer. In the present review, the biological functions of copper in the human body are presented, along with an overview of recent progress in our understanding of the biological applications and development of copper-containing materials. Furthermore, this review also provides the prospective on the challenges of those novel biomaterials for future clinical applications.

19.
Nanoscale ; 12(5): 2855-2874, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31965135

RESUMO

Hypoxia is a hallmark of the tumor microenvironment, which promotes the proliferation, metastasis and invasion of tumors and stimulates the resistance of cancer treatments, leading to the serious consequence of tumor recurrence. Many nanotechnology-based studies have been conducted to improve the efficacy of cancer treatments using a hypoxia strategy. This is usually achieved by (i) activating bioreductive prodrugs in the tumor hypoxic/exacerbated hypoxic microenvironment, or (ii) delivering therapeutic agents to hypoxic tumor tissue using targeting molecules. Normally, a good therapeutic effect can be expected upon modulating the hypoxic microenvironment for tumor treatments. To achieve this, various nanotechnology strategies based on overcoming hypoxia have been exploited to alleviate tumor hypoxia and enhance the therapeutic efficacy of tumor therapy, including (i) reducing oxygen consumption by inhibiting cell respiration, (ii) normalizing tumor vessels to promote blood flow in the tumor, (iii) carrying exogenous oxygen into the tumor, and (iv) generating oxygen in situ. The strategy of in situ oxygen production is refined, and the scope of this strategy is further expanded. Finally, the inspiration of using advanced nanotechnology in hypoxia-associated antitumor therapy guides the study of tumor hypoxia for clinical use.


Assuntos
Antineoplásicos/uso terapêutico , Nanotecnologia , Neoplasias , Pró-Fármacos/uso terapêutico , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Animais , Humanos , Neoplasias/irrigação sanguínea , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia
20.
ACS Nano ; 14(11): 14907-14918, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33111520

RESUMO

Vessel embolization is recommended as the first line treatment for unresectable hepatocellular carcinoma (HCC). However, owing to the imprecise vessel embolization and heterogeneous response performance among patients, its survival benefits are often compromised. Herein, we reported an innovative strategy to extensively embolize the tumor by triggering the coagulation cascade, and predict the embolization effect with vessel density assessment. We synthesized manganese dioxide (MnO2)/verteporfin (BPD) nanocomposites, in which BPD bound to the tumor vessel endothelial cells (TVECs) and MnO2 nanosheets served as the carrier. MnO2 was reduced to Mn2+ ions and self-assembled with BPD to produce nanoBPD, resulting in enhanced TVECs apoptosis and coagulation cascade compared to that with free BPD. Furthermore, multimodal imaging was used to visualize tumor vessel density, which can be used as a predictor to identify the patients who would benefit from embolization. Our findings describe a promising strategy for both tumor eradication and effect prediction to improve survival benefits in unresectable HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Nanopartículas , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Células Endoteliais , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Compostos de Manganês , Óxidos
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