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1.
J Biomech Eng ; 144(3)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34505142

RESUMO

Acoustic droplet vaporization (ADV) has been proven to enhance high intensity focused ultrasound (HIFU) thermal ablation of tumor. It has also been demonstrated that triggering droplets before HIFU exposure could be a potential way to control both the size and the shape of the thermal lesion. In this paper, a numerical model is proposed to predict the thermal lesion created in ADV enhanced HIFU treatment. Bubble oscillation was coupled into a viscoelastic medium in the model to more closely represent real applications in tissues. Several physical processes caused by continuous wave ultrasound and elevated temperature during the HIFU exposure were considered, including rectified diffusion, gas solubility variation with temperature in the medium, and boiling. Four droplet concentrations spanning two orders of magnitude were calculated. The bubble cloud formed from triggering of the droplets by the pulse wave ultrasound, along with the evolution of the shape and location of the bubble cloud and thermal lesion during the following continuous wave exposure was obtained. The increase of bubble void fraction caused by continuous wave exposure was found to be consistent with the experimental observation. With the increase of droplet concentration, the predicted bubble cloud shapes vary from tadpole to triangular and double triangular, while the thermal lesions move toward the transducer. The results show that the assumptions used in this model increased the accuracy of the results. This model may be used for parametrical study of ADV enhanced HIFU treatment and be further used for treatment planning and optimization in the future.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Microbolhas , Acústica , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Transdutores , Volatilização
2.
Int J Mol Sci ; 22(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576115

RESUMO

Immunotherapy has emerged as a therapeutic pillar in tumor treatment, but only a minority of patients get benefit. Overcoming the limitations of immunosuppressive environment is effective for immunotherapy. Moreover, host T cell activation and longevity within tumor are required for the long-term efficacy. In our previous study, a novel cryo-thermal therapy was developed to improve long-term survival in B16F10 melanoma and s.q. 4T1 breast cancer mouse models. We determined that cryo-thermal therapy induced Th1-dominant CD4+ T cell differentiation and the downregulation of Tregs in B16F10 model, contributing to tumor-specific and long-lasting immune protection. However, whether cryo-thermal therapy can affect the differentiation and function of T cells in a s.q. 4T1 model remains unknown. In this study, we also found that cryo-thermal therapy induced Th1-dominant differentiation of CD4+ T cells and the downregulation of effector Tregs. In particular, cryo-thermal therapy drove the fragility of Tregs and impaired their function. Furthermore, we discovered the downregulated level of serum tumor necrosis factor-α at the late stage after cryo-thermal therapy which played an important role in driving Treg fragility. Our findings revealed that cryo-thermal therapy could reprogram the suppressive environment and induce strong and durable antitumor immunity, which facilitate the development of combination strategies in immunotherapy.


Assuntos
Crioterapia , Regulação para Baixo , Neoplasias/imunologia , Neoplasias/terapia , Linfócitos T Reguladores/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Feminino , Terapia de Imunossupressão , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Testes de Neutralização , Fenótipo , Ablação por Radiofrequência , Fator de Necrose Tumoral alfa/sangue
3.
Biomed Eng Online ; 19(1): 44, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32522205

RESUMO

BACKGROUND: Restenosis remains a challenge in the treatment of atherosclerosis due to damage to the endothelial layer and induced proliferation of smooth muscle cells. A novel radiofrequency (RF) heating strategy was proposed to selectively ablate atherosclerosis plaque and to thermally inhibit the proliferation of smooth muscle cells while keeping the endothelial cells intact. METHODS: To realize the proposed strategy, a new radiofrequency balloon catheter, consisting of three ports, a three-channel tube, a balloon and an electrode patch, was designed. To evaluate the feasibility of this new design, a phantom experiment with thermocouples measuring temperatures with different voltages applied to the electrodes was conducted. A numerical model was established to obtain the 3D temperature distribution. The heating ability was also evaluated in ex vivo diseased artery samples. RESULTS: The experimental results showed that the highest temperature could be achieved in a distance from the surface of the balloon as designed. The temperature differences between the highest temperature at 0.78 mm and those of the surface reached 9.87 °C, 12.55 °C and 16.00 °C under applied 15 V, 17.5 V and 20 V heating, respectively. In the circumferential direction, the heating region (above 50 °C) spread from the middle of the two electrodes. The numerical results showed that the cooling effect counteracted the electrical energy deposition in the region close to the electrodes. The thermal lesion could be directed to cover the diseased media away from the catheter surface. The ex vivo heating experiment also confirmed the selective heating ability of the device. The temperature at the targeted site quickly reached the set value. The temperature of the external surface was higher than the inner wall surface temperature of the diseased artery lumen. CONCLUSION: Both the experimental and numerical results demonstrated the feasibility of the newly designed RF balloon catheter. The proposed RF microelectrodes heating together with the cooling water convection can realize the desired heating in the deeper site of the blood vessel wall while sparing the thin layer of the endothelium.


Assuntos
Angioplastia com Balão/instrumentação , Aterosclerose/terapia , Ondas de Rádio , Eletrodos , Imagens de Fantasmas , Temperatura
4.
Int J Hyperthermia ; 37(1): 843-853, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32654540

RESUMO

PURPOSE: In our previous study, a novel cryo-thermal therapy that could stimulate the maturation of innate immune cells to subsequently activate the CD4+Th1 cell-dominated antitumor response was developed. However, why cryo-thermal therapy can induce the maturation of innate immunity remains unknown. METHODS: In this study, western blot and ELISA were used to analyze the levels of damage-associated molecular patterns (DAMPs, including heat shock protein 70 (HSP70), calreticulin and high-mobility group box protein 1) in situ and in the peripheral blood at different times after cryo-thermal therapy or traditional radiofrequency ablation. The effects of these three DAMPs on myeloid-derived suppressor cells (MDSCs), dendritic cells (DCs) and macrophages were investigated by antibody neutralization in vitro. The phenotypic and functional changes in MDSCs, DCs and macrophages were analyzed using FACS and qRT-PCR. An anti-HSP70 antibody was injected intravenously at 6 h after cryo-thermal therapy on days 1 and 2 and mouse survival was monitored. RESULTS: Cryo-thermal therapy could trigger the release of DAMPs in situ and in the peripheral circulation, which could downregulate the proportion and suppressive signature of MDSCs, and promote the M1 macrophages polarization and DCs maturation. Among three DAMPs, HSP70 played the most evident role in M1 macrophage polarization. In vivo neutralization of HSP70 in the early stage of treatment could significantly decrease the survival rate of cryo-thermal therapy treated mice. CONCLUSIONS: Local cryo-thermal therapy not only destroyed solid tumors thermally and mechanically but also induced the release of a large amount of DAMPs to effectively trigger a systemic antitumor response.


Assuntos
Proteínas de Choque Térmico HSP70 , Neoplasias , Animais , Diferenciação Celular , Células Dendríticas , Imunidade Inata , Macrófagos , Camundongos
5.
Int J Hyperthermia ; 36(1): 408-420, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30892102

RESUMO

PURPOSE: We previously developed a novel cryo-thermal therapy to treat malignant mammary carcinoma and melanoma in a mouse model; long-term survival and CD4+ T cell orchestrating anti-tumor immune memory response were achieved. Moreover, cryo-thermal-induced CD4+ T cell differentiation into Th1 and CD4+CTL sub-lineages, in which M1 macrophage polarization played a direct, important role. In particular, cryo-thermal therapy triggered M1 macrophage polarization with up-regulated expression of C-X-C motif ligand 10 (CXCL10) and Interleukin 6 (IL-6). But whether CXCL10 and IL-6 contribute to CD4+ T cell-mediated anti-tumor immunity remains unclear. In this study, the role of cryo-thermal-induced CXCL10 and IL-6 in anti-tumor immunity was determined. METHODS: The level of CXCL10 and IL-6 in spleen and serum was determined by RT-PCR and ELISA on day 14 after cryo-thermal therapy. Splenic dendritic cells (DCs) and macrophages were isolated from cryo-thermal-treated mice on day 5 and 14, and the level of CXCL10 and IL-6 in macrophages and DCs was determined by ELISA. The transwell migration assay was performed to study immune cell migration. In vivo neutralization of CXCL10 or IL-6 was performed to investigate the phenotypic changes of immune cells. RESULTS: Cryo-thermal therapy induced M1 macrophage polarization with up-regulation of CXCL10 and IL-6 expression in spleen. CXCL10 and IL-6 promoted DCs migration and maturation, and subsequently promoted CD4+ T cell migration and differentiation into Th1 and CD4+ CTL, moreover, reduced myeloid-derived suppressor cells (MDSCs) accumulation. CONCLUSIONS: Cryo-thermal-induced CXCL10 and IL-6 created acute inflammatory environment to initiate a systemically cascading innate and adaptive anti-tumor immunity, which was more permissive for tumor eradication.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Quimiocina CXCL10/metabolismo , Interleucina-6/metabolismo , Macrófagos/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Camundongos
6.
Biomed Eng Online ; 17(1): 163, 2018 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-30373677

RESUMO

BACKGROUND: Bubbles formed by acoustic droplet vaporization (ADV) have proven to be an effective method for significant enlargement of the thermal lesions produced by high intensity focused ultrasound (HIFU). We investigated the influences of bubble cloud shape and droplet concentration on HIFU thermal lesions, as these relate to the ADV technique. METHODS: Unlike previous studies where the droplets were simultaneously vaporized with the HIFU exposure for thermal lesion formation, droplets were vaporized by pulse wave (PW) ultrasound prior to continuous wave (CW) ultrasound heating in this experimental study. Under different experimental conditions, we recorded and quantified by the image processing methods the morphology and size of the bubble clouds created and the corresponding thermal lesions formed. RESULTS: The results demonstrated that different ADV droplet concentrations produced a variety of thermal lesion shapes and sizes. The lesion volume could be increased using PW ultrasound followed by CW exposure, especially for higher droplet concentrations, e.g. 3.41 × 106/mL yielded a tenfold increase over that seen using CW alone. CONCLUSION: These findings could lead to optimization of HIFU therapy by selecting a bubble forming strategy and droplet concentrations, especially using lower ultrasound powers which is desirable in clinical applications.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Acústica , Simulação por Computador , Desenho de Equipamento , Fluorocarbonos/química , Gases , Temperatura Alta , Lipídeos/química , Microbolhas , Imagens de Fantasmas , Pressão , Processamento de Sinais Assistido por Computador , Transdutores , Ultrassonografia , Volatilização
7.
Int J Hyperthermia ; 34(3): 261-272, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28540834

RESUMO

In our previous studies, a novel tumour therapeutic modality of the cryo-thermal therapy has been developed leading to long-term survival in 4T1 murine mammary carcinoma model. The cryo-thermal therapy induced the strong acute inflammatory response and IL-6 was identified in an acute profile. In this study, we found that the cryo-thermal therapy triggered robust acute inflammatory response with high expression of IL-6 locally and systemically. The phenotypic maturation of dendritic cells (DCs) was induced by acute IL-6 following the treatment. The mature DCs promoted CD4+ T cell differentiation. Moreover, the production of interferon γ (IFN γ) in the serum and CD4+ T cells were both abrogated by IL-6 neutralisation following the treatment. Our findings revealed that the cryo-thermal therapy-induced acute IL-6 played an important role in initiating the cascading innate and adaptive anti-tumour immune responses, resulting in CD4+ T cell differentiation. It would be interesting to investigate acute IL-6 as an early indicator in predicating tumour therapeutic effect.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Interleucina-6/imunologia , Animais , Diferenciação Celular , Modelos Animais de Doenças , Camundongos
8.
Int J Hyperthermia ; 35(1): 79-89, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29865914

RESUMO

In our previous animal model study, we found that radiofrequency (RF) ablation of pre-frozen tumor resulted in improved therapeutic effects. To understand the underlying mechanisms and optimize the treatment protocol, the RF heating pattern in pre-frozen tissue was studied in this paper. Both ex vivo and in vivo experiments were conducted to compare the temperature profiles of RF heating with or without pre-freezing. Results showed that the heating rate of in vivo tissues was significantly higher with pre-freezing. However, little difference was observed in the heating rate of ex vivo tissues with or without pre-freezing. In the histopathologic analysis of in vivo tissues, both a larger ablation area and a wider transitional zone were found in the tissue with pre-freezing. To investigate the cause for the enhancement in RF heating, the parameters affecting the tissue temperature rise were studied. It was found that the electrical conductivity of in vivo tissue with pre-freezing was much higher at low frequencies, but little difference was found at the 460 kHz frequency commonly used in clinical applications. A finite element model for RF heating was developed and validated to fit the thermal conductivity of in vivo tissue including effects of pre-freezing and the associated blood perfusion rate. Results showed that the enhancement of the heating rate was primarily attributed to the decreased blood perfusion rate in the tissue with vascular damage caused by pre-freezing. The ablation volume was increased by 104% due to the reduced heat dissipation.


Assuntos
Criopreservação/métodos , Temperatura Alta/uso terapêutico , Neoplasias/radioterapia , Terapia por Radiofrequência , Animais , Ablação por Cateter/métodos , Modelos Animais , Neoplasias/patologia
9.
J Biomech Eng ; 139(9)2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28654938

RESUMO

Acoustic droplet vaporization has the potential to shorten treatment time of high-intensity focused ultrasound (HIFU) while minimizing the possible effects of microbubbles along the propagation path. Distribution of the bubbles formed from the droplets during the treatment is the major factor shaping the therapeutic region. A numerical model was proposed to simulate the bubble area evolution during this treatment. Using a linear acoustic equation to describe the ultrasound field, a threshold range was defined that determines the amount of bubbles vaporized in the treated area. Acoustic parameters, such as sound speed, acoustic attenuation coefficient, and density, were treated as a function of the bubble size distribution and the gas void fraction, which were related to the vaporized bubbles in the medium. An effective pressure factor was proposed to account for the influence of the existing bubbles on the vaporization of the nearby droplets. The factor was obtained by fitting one experimental result and was then used to calculate bubble clouds in other experimental cases. Comparing the simulation results to these other experiments validated the model. The dynamic change of the pressure and the bubble distribution after exposure to over 20 pulses of HIFU are obtained. It is found that the bubble area grows from a grainlike shape to a "tadpole," with comparable dimensions and shape to those observed in experiments. The process was highly dynamic with the shape of the bubble area changing with successive HIFU pulses and the focal pressure. The model was further used to predict the shape of the bubble region triggered by HIFU when a bubble wall pre-exists. The results showed that the bubble wall helps prevent droplet vaporization on the distal side of the wall and forms a particularly shaped region with bubbles. This simulation model has predictive potential that could be beneficial in applications, such as cancer treatment, by parametrically studying conditions associated with these treatments and designing treatment protocols.


Assuntos
Acústica , Ablação por Ultrassom Focalizado de Alta Intensidade , Modelos Teóricos , Pressão , Volatilização
10.
Biochem Biophys Res Commun ; 475(2): 154-60, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27181360

RESUMO

Chemotherapeutic efficacy is also regulated by the tumor microenvironment. IL-6 produced by TAMs and downstream IL-6/STAT3 signaling pathway is central regulator in chemotherapeutic response. The M2-like phenotype of TAMs is characterized by elevated iron uptake. Whether iron participates in chemo-resistance need to be elucidated. In the present study, we found that IL-6 participated in breast cancer chemoresistance. Local IL-6 paracrine loop acted as exogenous IL-6 rich niche for chemo-sensitive breast cancer cells, leading to de novo acquired drug resistance. Furthermore, Iron reinforced the IL-6 paracrine loop between TAMs and tumor cells resulting in enhanced chemo-resistance. Targeting iron metabolism could disturb the reciprocal interaction between tumor cells and TAMs, breaking the local IL-6 rich niche and blocking IL-6 signaling pathway, which could be promising strategy to overcome chemo-resistance.


Assuntos
Neoplasias da Mama/imunologia , Mama/imunologia , Resistencia a Medicamentos Antineoplásicos , Interleucina-6/imunologia , Ferro/imunologia , Macrófagos/imunologia , Animais , Antineoplásicos/farmacologia , Mama/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Polaridade Celular/efeitos dos fármacos , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Comunicação Parácrina/efeitos dos fármacos , Fator de Transcrição STAT3/imunologia
11.
Front Immunol ; 15: 1345046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827732

RESUMO

Introduction: Recently, more and more research illustrated the importance of inducing CD4+ T helper type (Th)-1 dominant immunity for the success of tumor immunotherapy. Our prior studies revealed the crucial role of CD4+ Th1 cells in orchestrating systemic and durable antitumor immunity, which contributes to the satisfactory outcomes of the novel cryo-thermal therapy in the B16F10 tumor model. However, the mechanism for maintaining the cryo-thermal therapy-mediated durable CD4+ Th1-dominant response remains uncovered. Additionally, cryo-thermal-induced early-stage CD4+ Th1-dominant T cell response showed a correlation with the favorable prognosis in patients with colorectal cancer liver metastasis (CRCLM). We hypothesized that CD4+ Th1-dominant differentiation induced during the early stage post cryo-thermal therapy would affect the balance of CD4+ subsets at the late phase. Methods: To understand the role of interferon (IFN)-γ, the major effector of Th1 subsets, in maintaining long-term CD4+ Th1-prone polarization, B16F10 melanoma model was established in this study and a monoclonal antibody was used at the early stage post cryo-thermal therapy for interferon (IFN)-γ signaling blockade, and the influence on the phenotypic and functional change of immune cells was evaluated. Results: IFNγ at the early stage after cryo-thermal therapy maintained long-lasting CD4+ Th1-prone immunity by directly controlling Th17, Tfh, and Tregs polarization, leading to the hyperactivation of Myeloid-derived suppressor cells (MDSCs) represented by abundant interleukin (IL)-1ß generation, and thereby further amplifying Th1 response. Discussion: Our finding emphasized the key role of early-phase IFNγ abundance post cryo-thermal therapy, which could be a biomarker for better prognosis after cryo-thermal therapy.


Assuntos
Diferenciação Celular , Interferon gama , Melanoma Experimental , Camundongos Endogâmicos C57BL , Células Th1 , Animais , Células Th1/imunologia , Camundongos , Interferon gama/metabolismo , Diferenciação Celular/imunologia , Melanoma Experimental/imunologia , Melanoma Experimental/terapia , Crioterapia/métodos , Linhagem Celular Tumoral , Feminino
12.
J Proteome Res ; 12(4): 1754-63, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-23445495

RESUMO

Metastasis is the main cause for death of breast cancer patients. However, the underlying mechanism is still poorly understood. Plasma membrane (PM) proteins play a key role in various biological processes, especially for cell migration. In this study, we used a set of well-characterized mammary mouse cell lines, 67NR, 168FARN, 4T1, representing the metastatic progression, to study the differentially expressed membrane proteins. These proteins were analyzed by a linear ion trap tandem mass spectrometry (LTQ-MS/MS) following cell surface biotinylation and streptavidin purification. A total of 1667 membrane proteins were identified, out of which 472 were characterized as differentially expressed with at least 2-fold change and p-value < 0.01. Functional clustering of the 472 proteins revealed that 178 of them were metabolic proteins. Finally, we focused on two metabolic proteins, fatty acid synthase (FASN) and NAD(P)H steroid dehydrogenase-like protein (NSDHL), which were validated by Western blot and immunofluorescence. We found that FASN and NSDHL translocated to the plasma membrane from the intracellular compartment, and their expressions increased from 67NR to 4T1. This alteration of localization along with differential expressions might be necessary for metastasis development. Potentially, FASN and NSDHL could serve as drug targets in new antimetastasis therapy.


Assuntos
3-Hidroxiesteroide Desidrogenases/metabolismo , Membrana Celular/metabolismo , Ácido Graxo Sintase Tipo I/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Proteômica/métodos , Animais , Western Blotting , Linhagem Celular Tumoral , Cromatografia Líquida , Proteínas de Membrana/metabolismo , Camundongos , Transporte Proteico , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
13.
J Proteome Res ; 12(6): 3000-9, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23675754

RESUMO

Recent studies suggest that biofluid-based metabonomics may identify metabolite markers promising for colorectal cancer (CRC) diagnosis. We report here a follow-up replication study, after a previous CRC metabonomics study, aiming to identify a distinct serum metabolic signature of CRC with diagnostic potential. Serum metabolites from newly diagnosed CRC patients (N = 101) and healthy subjects (N = 102) were profiled using gas chromatography time-of-flight mass spectrometry (GC-TOFMS) and ultraperformance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOFMS). Differential metabolites were identified with statistical tests of orthogonal partial least-squares-discriminant analysis (VIP > 1) and the Mann-Whitney U test (p < 0.05). With a total of 249 annotated serum metabolites, we were able to differentiate CRC patients from the healthy controls using an orthogonal partial least-squares-discriminant analysis (OPLS-DA) in a learning sample set of 62 CRC patients and 62 matched healthy controls. This established model was able to correctly assign the rest of the samples to the CRC or control groups in a validation set of 39 CRC patients and 40 healthy controls. Consistent with our findings from the previous study, we observed a distinct metabolic signature in CRC patients including tricarboxylic acid (TCA) cycle, urea cycle, glutamine, fatty acids, and gut flora metabolism. Our results demonstrated that a panel of serum metabolite markers is of great potential as a noninvasive diagnostic method for the detection of CRC.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/diagnóstico , Adulto , Idoso , Antígeno Carcinoembrionário/sangue , Estudos de Casos e Controles , Ciclo do Ácido Cítrico , Análise Discriminante , Ácidos Graxos/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glutamina/sangue , Humanos , Análise dos Mínimos Quadrados , Masculino , Metabolômica , Microbiota/fisiologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Estatísticas não Paramétricas , Ureia/sangue
14.
Biomed Eng Online ; 12: 127, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24325296

RESUMO

BACKGROUND: Radiofrequency ablation is a promising minimal invasive treatment for tumor. However, water loss due to evaporation has been a major issue blocking further RF energy transmission and correspondently eliminating the therapeutic outcome of the treatment. METHOD: A 2D symmetric cylindrical mathematical model coupling the transport of the electrical current, heat, and the evaporation process in the tissue, has been developed to simulate the treatment process and investigate the influence of the excessive evaporation of the water on the treatment. RESULTS: Our results show that the largest specific absorption rate (QSAR) occurs at the edge of the circular surface of the electrode. When excessive evaporation takes place, the water dehydration rate in this region is the highest, and after a certain time, the dehydrated tissue blocks the electrical energy transmission in the radial direction. It is found that there is an interval as long as 65 s between the beginning of the evaporation and the increase of the tissue impedance. The model is further used to investigate whether purposely terminating the treatment for a while allowing diffusion of the liquid water into the evaporated region would help. Results show it has no obvious improvement enlarging the treatment volume. Treatment with the cooled-tip electrode is also studied. It is found that the cooling conditions of the inside agent greatly affect the water loss pattern. When the convection coefficient of the cooling agent increases, excessive evaporation will start from near the central axis of the tissue cylinder instead of the edge of the electrode, and the coagulation volume obviously enlarges before a sudden increase of the impedance. It is also found that a higher convection coefficient will extend the treatment time. Though the sudden increase of the tissue impedance could be delayed by a larger convection coefficient; the rate of the impedance increase is also more dramatic compared to the case with smaller convection coefficient. CONCLUSION: The mathematical model simulates the water evaporation and diffusion during radiofrequency ablation and may be used for better clinical design of radiofrequency equipment and treatment protocol planning.


Assuntos
Técnicas de Ablação/métodos , Modelos Teóricos , Ondas de Rádio , Água/química , Difusão , Impedância Elétrica , Temperatura , Volatilização
15.
Mol Cell Proteomics ; 10(7): M110.004945, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21518826

RESUMO

Hepatocellular carcinoma (HCC) is a common malignancy in the world with high morbidity and mortality rate. Identification of novel biomarkers in HCC remains impeded primarily because of the heterogeneity of the disease in clinical presentations as well as the pathophysiological variations derived from underlying conditions such as cirrhosis and steatohepatitis. The aim of this study is to search for potential metabolite biomarkers of human HCC using serum and urine metabolomics approach. Sera and urine samples were collected from patients with HCC (n = 82), benign liver tumor patients (n = 24), and healthy controls (n = 71). Metabolite profiling was performed by gas chromatography time-of-flight mass spectrometry and ultra performance liquid chromatography-quadrupole time of flight mass spectrometry in conjunction with univariate and multivariate statistical analyses. Forty three serum metabolites and 31 urinary metabolites were identified in HCC patients involving several key metabolic pathways such as bile acids, free fatty acids, glycolysis, urea cycle, and methionine metabolism. Differentially expressed metabolites in HCC subjects, such as bile acids, histidine, and inosine are of great statistical significance and high fold changes, which warrant further validation as potential biomarkers for HCC. However, alterations of several bile acids seem to be affected by the condition of liver cirrhosis and hepatitis. Quantitative measurement and comparison of seven bile acids among benign liver tumor patients with liver cirrhosis and hepatitis, HCC patients with liver cirrhosis and hepatitis, HCC patients without liver cirrhosis and hepatitis, and healthy controls revealed that the abnormal levels of glycochenodeoxycholic acid, glycocholic acid, taurocholic acid, and chenodeoxycholic acid are associated with liver cirrhosis and hepatitis. HCC patients with alpha fetoprotein values lower than 20 ng/ml was successfully differentiated from healthy controls with an accuracy of 100% using a panel of metabolite markers. Our work shows that metabolomic profiling approach is a promising screening tool for the diagnosis and stratification of HCC patients.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Metaboloma , Adolescente , Adulto , Idoso , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/urina , Biomarcadores Tumorais/urina , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/urina , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/urina , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Componente Principal , Adulto Jovem , alfa-Fetoproteínas/metabolismo , alfa-Fetoproteínas/urina
16.
Artigo em Inglês | MEDLINE | ID: mdl-37015120

RESUMO

Novel multimode thermal therapy by freezing before radio-frequency heating has achieved a desirable therapeutic effect in liver cancer. Compared with surgical resection, ablation treatment has a relatively high risk of tumor recurrence. To monitor tumor progression after ablation, we developed a novel survival analysis framework for survival prediction and efficacy assessment. We extracted preoperative and postoperative MRI radiomics features and vision transformer-based deep learning features. We also combined the immune features extracted from peripheral blood immune responses using flow cytometry and routine blood tests before and after treatment. We selected features using random survival forest and improved the deep Cox mixture (DCM) for survival analysis. To properly accommodate multitype input features, we proposed a self-adapted fully connected layer for locally and globally representing features. We evaluated the method using our clinical dataset. Of note, the immune features rank the highest feature importance and contribute significantly to the prediction accuracy. The results showed a promising C td-index of 0.885 ±0.040 and an integrated Brier score of 0.041 ±0.014, which outperformed state-of-the-art method combinations of survival prediction. For each patient, individual survival probability was accurately predicted over time, which provided clinicians with trustable prognosis suggestions.

17.
Int J Comput Assist Radiol Surg ; 18(11): 1991-2000, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37391537

RESUMO

PURPOSE: The strong metal artifacts produced by the electrode needle cause poor image quality, thus preventing physicians from observing the surgical situation during the puncture process. To address this issue, we propose a metal artifact reduction and visualization framework for CT-guided ablation therapy of liver tumors. METHODS: Our framework contains a metal artifact reduction model and an ablation therapy visualization model. A two-stage generative adversarial network is proposed to reduce the metal artifacts of intraoperative CT images and avoid image blurring. To visualize the puncture process, the axis and tip of the needle are localized, and then the needle is rebuilt in 3D space intraoperatively. RESULTS: Experiments show that our proposed metal artifact reduction method achieves higher SSIM (0.891) and PSNR (26.920) values than the state-of-the-art methods. The accuracy of ablation needle reconstruction is 2.76 mm average in needle tip localization and 1.64° average in needle axis localization. CONCLUSION: We propose a novel metal artifact reduction and an ablation therapy visualization framework for CT-guided ablation therapy of liver cancer. The experiment results indicate that our approach can reduce metal artifacts and improve image quality. Furthermore, our proposed method demonstrates the potential for displaying the relative position of the tumor and the needle intraoperatively.

18.
Front Immunol ; 14: 1172362, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334386

RESUMO

Introduction: Multimode thermal therapy (MTT) is an innovative interventional therapy developed for the treatment of liver malignancies. When compared to the conventional radiofrequency ablation (RFA), MTT typically offers improved prognosis for patients. However, the effect of MTT on the peripheral immune environment and the mechanisms underlying the enhanced prognosis have yet to be explored. The aim of this study was to further investigate the mechanisms responsible for the difference in prognosis between the two therapies. Methods: In this study, peripheral blood samples were collected from four patients treated with MTT and two patients treated with RFA for liver malignancies at different time points before and after the treatment. Single cell sequencing was performed on the blood samples to compare and analyze the activation pathways of peripheral immune cells following the MTT and RFA treatment. Results: There was no significant effect of either therapy on the composition of immune cells in peripheral blood. However, the differential gene expression and pathway enrichment analysis demonstrated enhanced activation of T cells in the MTT group compared to the RFA group. In particular, there was a remarkable increase in TNF-α signaling via NF-κB, as well as the expression of IFN-α and IFN-γ in the CD8+ effector T (CD8+ Teff) cells subpopulation, when compared to the RFA group. This may be related to the upregulation of PI3KR1 expression after MTT, which promotes the activation of PI3K-AKT-mTOR pathway. Conclusion: This study confirmed that MTT could more effectively activate peripheral CD8+ Teff cells in patients compared with RFA and promote the effector function, thus resulting in a better prognosis. These results provide a theoretical basis for the clinical application of MTT therapy.


Assuntos
Ablação por Cateter , Neoplasias Hepáticas , Ablação por Radiofrequência , Humanos , Fosfatidilinositol 3-Quinases , Transcriptoma , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Ablação por Radiofrequência/métodos , Linfócitos T CD8-Positivos
19.
Proteomics ; 12(1): 32-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22065611

RESUMO

Secreted proteins play important roles in physiological and pathological processes. However, effective proteomic detection of low-abundant secreted proteins is often shielded by the presence of a large amount of intracellular proteins released from unavoidable dead cells during cell culture. In the present study, we applied lectin affinity capture approach to enrich the secreted proteins in the conditioned media (CM) of three human breast cell lines (MCF-10A, MCF-7, and MDA-MB-231). Lectin capture showed efficient enrichment of the secreted proteins in CM of all three cell lines and significantly increased the number of secreted proteins detected: from 183 to 292 for MCF-10A, 196 to 325 for MCF-7, and 194 to 368 for MDA-MB-231. Based on more comprehensive profiling of the secreted proteins, we identified 92 secreted proteins which were both upregulated in MCF-7 and MDA-MB-231, with 82 only found in lectin-captured samples. It should be noted that among these 82 potential biomarkers, 59 were not reported in the previous proteomic studies of breast cancer. These data indicate that the lectin capture approach is a powerful means to move toward more comprehensive analysis and comparison of secretomes.


Assuntos
Biomarcadores Tumorais/metabolismo , Cromatografia de Afinidade/métodos , Glicoproteínas/metabolismo , Lectinas/química , Proteoma/metabolismo , Biomarcadores Tumorais/isolamento & purificação , Neoplasias da Mama , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/química , Feminino , Glicoproteínas/isolamento & purificação , Humanos , Espectrometria de Massas , Proteoma/isolamento & purificação
20.
J Proteome Res ; 11(6): 3281-94, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22506683

RESUMO

Early diagnosis plays a decisive role in the outcome of colorectal cancer (CRC) therapy. The ex vivo culture of fresh CRC tissues and paired normal colorectal tissues provides a feasible way to explore potential serum biomarkers for CRC early detection under near-physiological conditions. In the present work, we applied a lectin affinity based approach to enrich and increase the detection number of secreted proteins in the conditioned media of cultured tissues. The captured proteins were then analyzed by the proteomic strategy of one-dimensional gel electrophoresis coupled to liquid chromatography-tandem mass spectrometry. By quantification with label-free spectral counting, we found 123 differentially expressed secreted proteins (DESPs) with 68 DESPs up-regulated in CRC tissues. EFEMP2, one of the top 10 up-regulated DESPs, was further validated by immunohistochemistry at tissue level and enzyme-linked immunosorbent assay at serum level. We found the expression level of EFEMP2 was dramatically increased in CRC patients, even at the early stage. Moreover, the diagnostic accuracy of EFEMP2 was superior to the established CRC biomarker carcinoembryonic antigen evidenced by the area under the receiver operating characteristic curve for the two biomarkers were 0.923 and 0.728, respectively. These results indicated EFEMP2 is a promising serum biomarker for CRC early detection.


Assuntos
Adenocarcinoma/sangue , Adenoma/sangue , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Proteínas da Matriz Extracelular/sangue , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adenoma/diagnóstico , Adenoma/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/isolamento & purificação , Estudos de Casos e Controles , Cromatografia de Afinidade , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Detecção Precoce de Câncer , Proteínas da Matriz Extracelular/isolamento & purificação , Feminino , Glicoproteínas/sangue , Glicoproteínas/isolamento & purificação , Humanos , Lectinas/química , Masculino , Pessoa de Meia-Idade , Proteoma/isolamento & purificação , Proteoma/metabolismo , Técnicas de Cultura de Tecidos , Regulação para Cima
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