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1.
Anal Chem ; 96(29): 11800-11808, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38990771

RESUMO

Organic Raman probes, including polymers and small molecules, have attracted great attention in biomedical imaging owing to their excellent biocompatibility. However, the development of organic Raman probes is usually hindered by a mismatch between their absorption spectra and wavelength-fixed excitation, which makes it difficult to achieve resonance excitation necessary to obtain strong Raman signals. Herein, we introduce a covalent organic framework (COF) into the fine absorption spectrum regulation of organic Raman probes, resulting in their significant Raman signal enhancement. In representative examples, a polymer poly(diketopyrrolopyrrole-p-phenylenediamine) (DPP-PD) and a small molecule azobenzene are transformed into the corresponding COF-structured Raman probes. Their absorption peaks show an accurate match of less than 5 nm with the NIR excitation. As such, the COF-structured Raman probes acquire highly sensitive bioimaging capabilities compared to their precursors with negligible signals. By further mechanism studies, we discover that the crystallinity and size of COFs directly affect the π-conjugation degree of Raman probes, thus changing their bandgaps and absorption spectra. Our study offers a universal and flexible method for improving the signal performance of organic Raman probes without changing their structural units, making it more convenient to obtain the highly sensitive organic Raman probes for in vivo bioimaging.


Assuntos
Análise Espectral Raman , Análise Espectral Raman/métodos , Animais , Humanos , Camundongos , Compostos Azo/química , Estruturas Metalorgânicas/química , Polímeros/química , Estrutura Molecular , Fenilenodiaminas/química
2.
J Transl Med ; 22(1): 198, 2024 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-38395884

RESUMO

BACKGROUND: Angiogenesis inhibitors have been identified to improve the efficacy of immunotherapy in recent studies. However, the delayed therapeutic effect of immunotherapy poses challenges in treatment planning. Therefore, this study aims to explore the potential of non-invasive imaging techniques, specifically intravoxel-incoherent-motion diffusion-weighted imaging (IVIM-DWI) and blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), in detecting the anti-tumor response to the combination therapy involving immune checkpoint blockade therapy and anti-angiogenesis therapy in a tumor-bearing animal model. METHODS: The C57BL/6 mice were implanted with murine MC-38 cells to establish colon cancer xenograft model, and randomly divided into the control group, anti-PD-1 therapy group, and combination therapy group (VEGFR-2 inhibitor combined with anti-PD-1 antibody treatment). All mice were imaged before and, on the 3rd, 6th, 9th, and 12th day after administration, and pathological examinations were conducted at the same time points. RESULTS: The combination therapy group effectively suppressed tumor growth, exhibiting a significantly higher tumor inhibition rate of 69.96% compared to the anti-PD-1 group (56.71%). The f value and D* value of IVIM-DWI exhibit advantages in reflecting tumor angiogenesis. The D* value showed the highest correlation with CD31 (r = 0.702, P = 0.001), and the f value demonstrated the closest correlation with vessel maturity (r = 0.693, P = 0.001). While the BOLD-MRI parameter, R2* value, shows the highest correlation with Hif-1α(r = 0.778, P < 0.001), indicating the capability of BOLD-MRI to evaluate tumor hypoxia. In addition, the D value of IVIM-DWI is closely related to tumor cell proliferation, apoptosis, and infiltration of lymphocytes. The D value was highly correlated with Ki-67 (r = - 0.792, P < 0.001), TUNEL (r = 0.910, P < 0.001) and CD8a (r = 0.918, P < 0.001). CONCLUSIONS: The combination of VEGFR-2 inhibitors with PD-1 immunotherapy shows a synergistic anti-tumor effect on the mouse colon cancer model. IVIM-DWI and BOLD-MRI are expected to be used as non-invasive approaches to provide imaging-based evidence for tumor response detection and efficacy evaluation.


Assuntos
Neoplasias do Colo , Inibidores de Checkpoint Imunológico , Receptor de Morte Celular Programada 1 , Animais , Humanos , Camundongos , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Inibidores de Checkpoint Imunológico/uso terapêutico
3.
BMC Cancer ; 24(1): 458, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609917

RESUMO

BACKGROUND: The identification of survival predictors is crucial for early intervention to improve outcome in acute myeloid leukemia (AML). This study aim to identify chest computed tomography (CT)-derived features to predict prognosis for acute myeloid leukemia (AML). METHODS: 952 patients with pathologically-confirmed AML were retrospectively enrolled between 2010 and 2020. CT-derived features (including body composition and subcutaneous fat features), were obtained from the initial chest CT images and were used to build models to predict the prognosis. A CT-derived MSF nomogram was constructed using multivariate Cox regression incorporating CT-based features. The performance of the prediction models was assessed with discrimination, calibration, decision curves and improvements. RESULTS: Three CT-derived features, including myosarcopenia, spleen_CTV, and SF_CTV (MSF) were identified as the independent predictors for prognosis in AML (P < 0.01). A CT-MSF nomogram showed a performance with AUCs of 0.717, 0.794, 0.796 and 0.792 for predicting the 1-, 2-, 3-, and 5-year overall survival (OS) probabilities in the validation cohort, which were significantly higher than the ELN risk model. Moreover, a new MSN stratification system (MSF nomogram plus ELN risk model) could stratify patients into new high, intermediate and low risk group. Patients with high MSN risk may benefit from intensive treatment (P = 0.0011). CONCLUSIONS: In summary, the chest CT-MSF nomogram, integrating myosarcopenia, spleen_CTV, and SF_CTV features, could be used to predict prognosis of AML.


Assuntos
Leucemia Mieloide Aguda , Nomogramas , Humanos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Área Sob a Curva , Leucemia Mieloide Aguda/diagnóstico por imagem
4.
Eur Radiol ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907098

RESUMO

OBJECTIVES: An easy-to-implement MRI model for predicting partial response (PR) postradiotherapy for diffuse intrinsic pontine glioma (DIPG) is lacking. Utilizing quantitative T2 signal intensity and introducing a visual evaluation method based on T2 signal intensity heterogeneity, and compared MRI radiomic models for predicting radiotherapy response in pediatric patients with DIPG. METHODS: We retrospectively included patients with brainstem gliomas aged ≤ 18 years admitted between July 2011 and March 2023. Applying Response Assessment in Pediatric Neuro-Oncology criteria, we categorized patients into PR and non-PR groups. For qualitative analysis, tumor heterogeneity vision was classified into four grades based on T2-weighted images. Quantitative analysis included the relative T2 signal intensity ratio (rT2SR), extra pons volume ratio, and tumor ring-enhancement volume. Radiomic features were extracted from T2-weighted and T1-enhanced images of volumes of interest. Univariate analysis was used to identify independent variables related to PR. Multivariate logistic regression was performed using significant variables (p < 0.05) from univariate analysis. RESULTS: Of 140 patients (training n = 109, and test n = 31), 64 (45.7%) achieved PR. The AUC of the predictive model with extrapontine volume ratio, rT2SRmax-min (rT2SRdif), and grade was 0.89. The AUCs of the T2-weighted and T1WI-enhanced models with radiomic signatures were 0.84 and 0.81, respectively. For the 31 DIPG test sets, the AUCs were 0.91, 0.83, and 0.81, for the models incorporating the quantitative features, radiomic model (T2-weighted images, and T1W1-enhanced images), respectively. CONCLUSION: Combining T2-weighted quantification with qualitative and extrapontine volume ratios reliably predicted pediatric DIPG radiotherapy response. CLINICAL RELEVANCE STATEMENT: Combining T2-weighted quantification with qualitative and extrapontine volume ratios can accurately predict diffuse intrinsic pontine glioma (DIPG) radiotherapy response, which may facilitate personalized treatment and prognostic assessment for patients with DIPG. KEY POINTS: Early identification is crucial for radiotherapy response and risk stratification in diffuse intrinsic pontine glioma. The model using tumor heterogeneity and quantitative T2 signal metrics achieved an AUC of 0.91. Using a combination of parameters can effectively predict radiotherapy response in this population.

5.
Environ Res ; 250: 118500, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38387492

RESUMO

Arsenic pollution is a challenging environmental issue caused by arsenic-bearing wastes from nonferrous metallurgy. Oxidative precipitation via introducing O2 into an ionic Fe(II)-As(V) solution is an advanced method for arsenic immobilization. However, the underlying mechanism is still not well understood. This study proposed a mechanism for scorodite formation by oxidative precipitation, and its thermodynamics were calculated using Gaussian software. Scorodite formation was divided into three stages: precursor formation (3-90 min), oxidative conversion (90-270 min) and crystallization (270-720 min) from the variation in precipitates and solution characterization and parameters such as initial pH, arsenic concentration, and ferrous dosage. In the scorodite formation mechanism, the precursors originate from the coordination polymerization of aqueous Fe(H2O)62+ and H2AsO4-, which contributes to the oxidative conversion of coordinated polymers ([Fe(H2O)4(H2O)]nn+) to basic Fe(H2O)2AsO4 until regular octahedral crystals are formed via nucleation and growth during crystallization. The ΔrGmθ for polymerization varied from -491.96 kJ mol-1 to -33.30 kJ mol-1, and the ΔrGmθ of oxidative conversion changed from -982.16 kJ mol-1 to -224.82 kJ mol-1, demonstrating the feasibility in scorodite formation. This research is significant for understanding scorodite formation in As(V) solutions. It can provide schemes for controlling and modifying the conditions of arsenic-bearing waste immobilization in the laboratories and industries.


Assuntos
Arsênio , Precipitação Química , Oxirredução , Termodinâmica , Arsênio/química , Arsênio/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
6.
Neurosurg Rev ; 47(1): 212, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727935

RESUMO

We aimed to evaluate the relationship between imaging features, therapeutic responses (comparative cross-product and volumetric measurements), and overall survival (OS) in pediatric diffuse intrinsic pontine glioma (DIPG). A total of 134 patients (≤ 18 years) diagnosed with DIPG were included. Univariate and multivariate analyses were performed to evaluate correlations of clinical and imaging features and therapeutic responses with OS. The correlation between cross-product (CP) and volume thresholds in partial response (PR) was evaluated by linear regression. The log-rank test was used to compare OS patients with discordant therapeutic response classifications and those with concordant classifications. In univariate analysis, characteristics related to worse OS included lower Karnofsky, larger extrapontine extension, ring-enhancement, necrosis, non-PR, and increased ring enhancement post-radiotherapy. In the multivariate analysis, Karnofsky, necrosis, extrapontine extension, and therapeutic response can predict OS. A 25% CP reduction (PR) correlated with a 32% volume reduction (R2 = 0.888). Eight patients had discordant therapeutic response classifications according to CP (25%) and volume (32%). This eight patients' median survival time was 13.0 months, significantly higher than that in the non-PR group (8.9 months), in which responses were consistently classified as non-PR based on CP (25%) and volume (32%). We identified correlations between imaging features, therapeutic responses, and OS; this information is crucial for future clinical trials. Tumor volume may represent the DIPG growth pattern more accurately than CP measurement and can be used to evaluate therapeutic response.


Assuntos
Neoplasias do Tronco Encefálico , Glioma Pontino Intrínseco Difuso , Humanos , Neoplasias do Tronco Encefálico/diagnóstico por imagem , Neoplasias do Tronco Encefálico/terapia , Neoplasias do Tronco Encefálico/mortalidade , Neoplasias do Tronco Encefálico/patologia , Masculino , Criança , Feminino , Adolescente , Glioma Pontino Intrínseco Difuso/terapia , Pré-Escolar , Resultado do Tratamento , Imageamento por Ressonância Magnética , Lactente , Estudos Retrospectivos , Glioma/terapia , Glioma/patologia , Glioma/diagnóstico por imagem , Glioma/mortalidade
7.
Ecotoxicol Environ Saf ; 249: 114412, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527847

RESUMO

Polystyrene nanoplastics (PS-NPs) are typical accumulated nanoplastics in the marine environment and organisms, and have strong potential risks to marine ecological environment and human health. MiRNAs could respond to and participate in the response process of environmental stressors. However, the response of miRNAs to nanoplastics has not been fully explored. In this study, miRNA responses of digestive glands in mussels Mytilus galloprovincialis treated by 200 nm PS-NPs (20, 200, 2000 µg/L) for 7 days were characterized by BGISEQ-500 deep sequencing and bioinformatics analysis, along with histopathological quantification with planimetric parameters on hematoxylin and eosin (H&E) staining. Results showed that one novel miRNA (novel_mir63) and seven known miRNAs (miR-34_2, miR-34_5, miR-281_8, let-7-5p_6, miR-10, miR-124, miR-29b-3p) were significantly (adjusted P-value < 0.05) differentially expressed after PS-NPs treatments, and most of them were down-regulated expect for novel_mir63 and miR-34_2. Function analysis of target genes corresponding to these differentially expressed miRNAs indicated that PS-NPs disturbed the process related to metabolism, aging, cardiac function, neural excitation, and repairment. Among them, acetyl-CoA C-acetyltransferase and purine metabolism pathway played vital connection roles. Meanwhile, significantly morphology changes of digestive tubes obtained from H&E stained sections also implied severely disrupted metabolic capability in digestive glands, reflected by significantly increased mean diverticular radius (MDR) and mean luminal radius (MLR) values and the ratio of MLR to mean epithelial thickness (MET), and significantly decreased MET value and MET/MDR. Overall, these findings have revealed new characterization of miRNAs and their target genes in mussel M. galloprovincialis under PS-NPs stress, and provide important clues to further elucidate the toxicity mechanisms of PS-NPs.


Assuntos
MicroRNAs , Mytilus , Poluentes Químicos da Água , Animais , Humanos , Poliestirenos/toxicidade , Poliestirenos/metabolismo , Mytilus/metabolismo , Microplásticos/toxicidade , Microplásticos/metabolismo , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
8.
Nano Lett ; 22(23): 9424-9433, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36378880

RESUMO

The intraoperative imaging applications of a large number of Raman probes are hampered by the overlap of their signals with the background Raman signals generated by biological tissues. Here, we describe a molecular planarization strategy for adjusting the Raman shift of these Raman probes to avoid interference. Using this strategy, we modify the backbone of thiophene polymer-poly(3-hexylthiophene) (P3HT), and obtain the adjacent thiophene units planarized polycyclopenta[2,1-b;3,4-b']dithiophene (PCPDT). Compared with P3HT whose signal is disturbed by the Raman signal of lipids in tissues, PCPDT exhibits a 60 cm-1 blueshift in its characteristic signal. Therefore, the PCPDT probe successfully avoids the signal of lipids, and achieves intraoperative imaging of lymph nodes and tumor micrometastasis as small as 0.30 × 0.36 mm. In summary, our study presents a concise molecular planarization strategy for regulating the signal shift of Raman probes, and brings a tunable thiophene polymer probe for high-precision intraoperative Raman imaging.


Assuntos
Micrometástase de Neoplasia , Análise Espectral Raman , Humanos , Análise Espectral Raman/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Polímeros/química , Tiofenos , Lipídeos
9.
Angew Chem Int Ed Engl ; 62(10): e202215387, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36479802

RESUMO

Cell-specific aptamers offer a powerful tool to study membrane receptors at the single-molecule level. Most target receptors of aptamers are highly expressed on the cell surface, but difficult to analyze in situ because of dense distribution and fast velocity. Therefore, we herein propose a random sampling-based analysis strategy termed ligand dilution analysis (LDA) for easily implemented aptamer-based receptor study. Receptor density on the cell surface can be calculated based on a regression model. By using a synergistic ligand dilution design, colocalization and differentiation of aptamer and monoclonal antibody (mAb) binding on a single receptor can be realized. Once this is accomplished, precise binding site and detailed aptamer-receptor binding mode can be further determined using molecular docking and molecular dynamics simulation. The ligand dilution strategy also sets the stage for an aptamer-based dynamics analysis of two- and three-dimensional motion and fluctuation of highly expressed receptors on the live cell membrane.


Assuntos
Aptâmeros de Nucleotídeos , Ligantes , Simulação de Acoplamento Molecular , Aptâmeros de Nucleotídeos/química , Sítios de Ligação , Ligação Proteica , Técnica de Seleção de Aptâmeros
10.
Small ; 18(12): e2106925, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35092156

RESUMO

Raman imaging is a powerful tool for the diagnosis of cancers and visualization of various biological processes. Polymers possessing excellent biocompatibility are promising probes for Raman imaging. However, few polymers are reported to serve as Raman probes for in vivo imaging, mainly due to the intrinsic weak Raman signal intensity and fluorescence interference of these polymers. Herein, a poly(indacenodithiophene-benzothiadiazole) (IDT-BT) polymer is presented, which emits unprecedentedly strong Raman signals under the near-infrared wavelength (785 nm) excitation, thus functioning as a Raman probe for ultrasensitive in vivo Raman imaging. Further mechanistic studies unveil that the unique Raman feature of the IDT-BT polymer relies on molecularly regulating its absorbance edge adjacent to the desired excitation wavelength, thus avoiding fluorescence interference and simultaneously emitting strong Raman scattering under preresonant excitation. Taking advantage of this discipline, the IDT-BT polymeric probe successfully realizes intraoperative Raman imaging of micrometastasis as small as 0.3 mm × 0.3 mm, comparable to the most sensitive Raman probes currently reported. Impressively, the IDT-BT enables noninvasive microvascular imaging, which is not achieved using other Raman probes. This work opens a new avenue toward the development of polymeric Raman probes for in vivo Raman imaging.


Assuntos
Diagnóstico por Imagem , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Polímeros , Análise Espectral Raman/métodos
11.
Small ; 18(41): e2203227, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36026551

RESUMO

Combined treatment of immunotherapy and radiotherapy shows promising therapeutic effects for the regression of a variety of cancers. However, even multi-modality therapies often fail to antagonize the regression of large tumors due to the extremely immunosuppressive tumor microenvironment (TME). Here, a radioimmunotherapeutic paradigm based on stimulator of interferon genes (STING)-dependent signaling is applied to preclude large tumor progression by utilizing the metal-cyclic dinucleotide (CDN) nanoplatform, which integrates STING agonist c-di-AMP and immunomodulating microelement manganese (II) within the tannic acid nanostructure (TMA-NPs). As observed by magnetic resonance imaging, the localized administration of TMA-NPs effectively relieves hypoxia within TME and causes radical oxygen species overproduction and apoptosis in cancer cells after exposure to X-ray irradiation. The DNA fragments released from the apoptotic cells after the combined treatment augment the production of endogenous CDNs in cancer cells, hence significantly activating the STING-mediated pathway for stronger anti-tumor immunity. The localized therapy of TMA-NPs + X-ray not only inhibits the primary large tumor progression but also retards distant tumor growth by promoting dendritic cell maturation and activating cytotoxic immune cells whil suppressing immunosuppressive cells. Therefore, this work represents the combinatorial potency of TMA-NPs and X-rays on large tumor regression through strengthened STING-mediated radioimmunotherapeutics.


Assuntos
Neoplasias , Radioimunoterapia , Humanos , Imunoterapia , Interferons , Manganês , Proteínas de Membrana/química , Neoplasias/patologia , Oxigênio , Taninos , Microambiente Tumoral
12.
J Nanobiotechnology ; 20(1): 104, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246149

RESUMO

BACKGROUND: Hypoxia is an important factor that contributes to chemoresistance and metastasis in triple negative breast cancer (TNBC), and alleviating hypoxia microenvironment can enhance the anti-tumor efficacy and also inhibit tumor invasion. METHODS: A near-infrared (NIR) responsive on-demand oxygen releasing nanoplatform (O2-PPSiI) was successfully synthesized by a two-stage self-assembly process to overcome the hypoxia-induced tumor chemoresistance and metastasis. We embedded drug-loaded poly (lactic-co-glycolic acid) cores into an ultrathin silica shell attached with paramagnetic Gd-DTPA to develop a Magnetic Resonance Imaging (MRI)-guided NIR-responsive on-demand drug releasing nanosystem, where indocyanine green was used as a photothermal converter to trigger the oxygen and drug release under NIR irradiation. RESULTS: The near-infrared responsive on-demand oxygen releasing nanoplatform O2-PPSiI was chemically synthesized in this study by a two-stage self-assembly process, which could deliver oxygen and release it under NIR irradiation to relieve hypoxia, improving the therapeutic effect of chemotherapy and suppressed tumor metastasis. This smart design achieves the following advantages: (i) the O2 in this nanosystem can be precisely released by an NIR-responsive silica shell rupture; (ii) the dynamic biodistribution process of O2-PPSiI was monitored in real-time and quantitatively analyzed via sensitive MR imaging of the tumor; (iii) O2-PPSiI could alleviate tumor hypoxia by releasing O2 within the tumor upon NIR laser excitation; (iv) The migration and invasion abilities of the TNBC tumor were weakened by inhibiting the process of EMT as a result of the synergistic therapy of NIR-triggered O2-PPSiI. CONCLUSIONS: Our work proposes a smart tactic guided by MRI and presents a valid approach for the reasonable design of NIR-responsive on-demand drug-releasing nanomedicine systems for precise theranostics in TNBC.


Assuntos
Nanopartículas , Fotoquimioterapia , Neoplasias de Mama Triplo Negativas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Hipóxia/diagnóstico por imagem , Hipóxia/tratamento farmacológico , Imageamento por Ressonância Magnética , Nanopartículas/uso terapêutico , Oxigênio/farmacologia , Medicina de Precisão , Distribuição Tecidual , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral
13.
Opt Lett ; 46(17): 4128-4131, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469956

RESUMO

The erbium-doped lithium niobate on insulator (Er:LNOI) platform has great promise in the application of telecommunication, microwave photonics, and quantum photonics, due to its excellent electro-optic, piezo-electric, nonlinear nature, as well as the gain characteristics in the telecommunication C-band. Here, we report a single-frequency Er:LNOI integrated laser based on a dual-cavity structure. Facilitated by the Vernier effect and gain competition, the single-frequency laser can operate stably at 1531 nm wavelength with a 1484 nm pump laser. The output laser has a power of 0.31 µW, a linewidth of 1.2 MHz, and a side mode suppression ratio of 31 dB. Our work allows the direct integration of this laser source with existing LNOI components and paves the way for a fully integrated LNOI system.

14.
Opt Express ; 28(10): 14933-14947, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403526

RESUMO

Dissipative Kerr solitons (DKS) in high-Q microresonators have attracted considerable attention for their broadband optical frequency combs and ultra-short pulse generation. Owing to thermal effects, complicated tuning strategies are required to generate and sustain the single-soliton state in microresonators. In this paper, we propose a novel microresonator scheme based on the Fabry-Pérot fiber resonator and single-layer graphene saturable absorber (SA) and demonstrate that this design allows deterministic single-soliton generation without frequency tuning and has strong robustness against pump perturbation. The soliton range and thermal instability of the proposed device are also discussed. This work facilitates a novel nonlinear platform connecting high-Q microresonators and conventional SA-assisted mode-locking operations.

15.
Nano Lett ; 19(5): 3344-3352, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30974946

RESUMO

Bypass signaling activation plays a crucial role in the acquired resistance of gefitinib, the first targeted drug in the clinic to treat advanced non-small cell lung cancer. Although the inactivation of bypass signaling by small-molecule inhibitors or monoclonal antibodies may overcome gefitinib resistance, their clinical use has been limited by the complex production process and off-target toxicity. Here we show CuS nanoparticles (NPs) behaved as a photodynamic nanoswitch to specifically abrogate overactive bypass signaling in resistant tumor cells without interfering with the same signal pathways in normal cells. In representative insulin growth factor-1 receptor (IGF1R) bypass activation-induced gefitinib resistant tumors, CuS NPs upon near-infrared laser irradiation locally elevated reactive oxygen species (ROS) level in tumor cells, leading to the blockage of bypass IGF1R and its downstream AKT/ERK/NF-κB signaling cascades. Consequently, laser-irradiated CuS NPs sensitized tumors to gefitinib treatment and prolonged the survival of mice with no obvious toxicity. Laser-irradiated CuS NPs may serve as a simple and safe nanomedicine strategy to overcome bypass activation-induced gefitinib resistance in a specific and controllable manner and provide insights into the treatment of a myriad of other resistant tumors in the field of cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Nanopartículas/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cobre/química , Cobre/farmacologia , Humanos , Camundongos , Mutação , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Angiogenesis ; 22(3): 457-470, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31147887

RESUMO

OBJECTIVE: This study aims to explore the feasibility of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and blood oxygen level-dependent magnetic resonance imaging (BOLD-MRI) in assessing vessel function and tumour aggressiveness during anti-angiogenesis treatment. MATERIALS AND METHODS: A colon cancer xenograft model was established in BALB/C nude mice with the HCT116 cell line. Sixteen mice were randomly divided into Group A and Group B, which were treated with saline or bevacizumab by intraperitoneal injection on the 1st, 4th, 7th, 10th and 13th days and underwent DCE-MRI and BOLD-MRI examinations before and on the 3rd, 6th, 9th, 12th and 15th days after treatment. Group C was treated with oxaliplatin monotherapy, and Group D was treated with bevacizumab and oxaliplatin as a point of comparison for therapeutic effects. The pathological examinations included HE, HIF-1α, fibronectin and TUNEL staining, as well as α-SMA and CD31 double staining. One-way analysis of variance and correlation analysis were the main methods used for statistical analysis. RESULTS: Group D manifested the highest tumour inhibition rate and smallest tumour volume on day 15, followed by Group C, Group B and Group A. Ktrans (F = 81.386, P < 0.001), Kep (F = 45.901, P < 0.001), Ve (F = 384.290, P < 0.001) and R2* values (F = 89.323, P < 0.001) showed meaningful trends with time in Group B but not Group A. The Ktrans values and tumour vessel maturity index (VMI) were higher than baseline values 3-12 days after bevacizumab treatment. The CD31 positive staining rate and VMI had the strongest correlations with Ktrans values, followed by AUC180, Ve and Kep values. The R2* value positively correlated with the positive staining rates of HIF-1α and fibronectin. CONCLUSION: Intermittent application of low-dose anti-angiogenic inhibitor treatment may help improve the effect of chemotherapy by reducing hypoxia-related treatment resistance and improving drug delivery. DCE-MRI is useful for evaluating vessel maturity and vascular normalization, while BOLD-MRI may help to predict tumour hypoxia and metastatic potential after anti-vascular treatment.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Imageamento por Ressonância Magnética , Neovascularização Patológica/tratamento farmacológico , Microambiente Tumoral , Inibidores da Angiogênese/farmacologia , Animais , Feminino , Células HCT116 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
18.
Crit Rev Food Sci Nutr ; 59(sup1): S116-S129, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30580553

RESUMO

Excess alcohol exposure leads to alcoholic liver disease (ALD), a predominant cause of liver-related morbidity and mortality worldwide. In the past decade, increasing attention has been paid to understand the association between n-3 polyunsaturated fatty acids (n-3 PUFAs) and ALD. In this review, we summarize the metabolism of n-3 PUFAs, animal model of ALD, and the findings from recent studies determining the role of n-3 PUFAs in ALD as a possible treatment. The animal models of acute ethanol exposure, chronic ethanol exposure and chronic-plus-single binge ethanol feeding have been widely used to explore the impact of n-3 PUFAs. Although the results of studies regarding the role of n-3 PUFAs in ALD have been inconsistent or controversial, increasing evidence has demonstrated that n-3 PUFAs may be useful in alleviating alcoholic steatosis and alcohol-induced liver injury through multiple mechanisms, including decreased de novo lipogenesis and lipid mobilization from adipose tissue, enhanced mitochondrial fatty acid ß-oxidation, reduced hepatic inflammation and oxidative stress, and promoted intestinal homeostasis, positively suggesting that n-3 PUFAs might be promising for the management of ALD. The oxidation of n-3 PUFAs ex vivo in an experimental diet was rarely considered in most n-3 PUFA-related studies, likely contributing to the inconsistent results. Thus, the role of n-3 PUFAs in ALD deserves greater research efforts and remains to be evaluated in randomized, placebo-controlled clinic trial. ABBREVIATION AA arachidonic acid ACC acetyl-CoA carboxylase ACLY ATP-citrate lyase ACO acyl-CoA oxidase ALA α-linolenic acid ALD alcoholic liver disease ALP alkaline phosphatase ALT alanine aminotransferase AMPK AMP-activated protein kinase AST aspartate aminotransferase ATGL adipose triglyceride lipase cAMP cyclic adenosine 3',5'-monophosphate COX cyclooxygenases CPT1 carnitine palmitoyltransferase 1 CYP2E1 cytochrome P450 2E1 DGAT2 diacylglycerol acyltransferase 2 DGLA dihomo-γ-linolenic acid DHA docosahexaenoic acid DPA docosapentaenoic acid DTA docosatetraenoic acid EPA eicosapentaenoic acid ER endoplasmic reticulum ETA eicosatetraenoic acid FAS fatty acid synthase FATPs fatty acid transporter proteins GLA,γ linolenic acid GPR120 G protein-coupled receptor 120 GSH glutathione; H&E haematoxylin-eosin; HO-1 heme oxygenase-1; HSL hormone-sensitive lipase; IL-6 interleukin-6 iNOS nitric oxide synthase LA linoleic acid LBP lipopolysaccharide binding protein LOX lipoxygenases LXR liver X receptor LXREs LXR response elements MCP-1 monocyte chemotactic protein-1 MTP microsomal triglyceride transfer protein MUFA monounsaturated fatty acids MyD88 myeloid differentiation factor 88 n-3 PUFAs omega-3 polyunsaturated fatty acid NAFLD nonalcoholic fatty liver disease NASH nonalcoholic steatohepatitis NF-κB transcription factor nuclear factor κB PDE3B phosphodiesterase 3B PPAR peroxisome proliferator-activated receptor ROS reactive oxygen species RXR retinoid X receptor SCD-1 stearyl CoA desaturase-1 SDA stearidonic acid SFA saturated fatty acids SIRT1 sirtuin 1 SOD superoxide dismutase SREBP sterol regulatory element-binding protein TB total bilirubin TC total cholesterol TG triacylglycerol TLR4 Toll-like receptor-4 TNF-α tumor necrosis factor-α VLDLR very low-density lipoprotein receptor WT wild type; ZO-1 zonula occludens-1.


Assuntos
Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-3/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas , Modelos Animais de Doenças , Etanol/efeitos adversos , Ácidos Graxos Ômega-3/farmacologia , Fígado Gorduroso/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Homeostase , Humanos , Inflamação/tratamento farmacológico , Mobilização Lipídica , Lipogênese , Fígado/efeitos dos fármacos , Fígado/metabolismo , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Permeabilidade
19.
Med Sci Monit ; 25: 3485-3494, 2019 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-31077263

RESUMO

BACKGROUND Numerous studies have explored diagnosis of pulmonary nodules using perfusion computed tomography (CT); however, findings were not always consistent between studies. Th e present study aimed to summarize evidence on the diagnostic value of perfusion CT for distinguishing between lung cancer and benign lesions. MATERIAL AND METHODS We performed a systematic literature search on lung cancer and benign pulmonary lesions performed with perfusion CT. The searches were undertaken in English or Chinese language in Medline, PubMed, Embase, Cochrane Library, Web of Science, and China National Knowledge Infrastructure database from Jan 2010 to Nov 2018. Standardized mean differences (SMDs) and 95% confidence intervals (CIs) of blood volume (BV), blood flow (BF), mean transit time (MTT), and permeability surface (PS) were calculated using Review Manager 5.3. Publication bias, sensitivity, specificity, and the area under the curve (AUC) were calculated using Stata12.0. RESULTS Fourteen studies comprising 1032 malignant and 447 benign pulmonary lesions were analyzed. Lung cancer had higher BV, BF, MTT, and PS values than benign lesions. SMDs and 95% CIs of BV, BF, MTT, and PS were 2.29 (1.43, 3.16), 0.50 (0.14, 0.86), 0.55 (0.39, 0.72), and 1.21 (0.87, 1.56), respectively. AUC values of BV and PS were 0.92 (0.90, 0.94) and 0.83 (0.80, 0.86), respectively. CONCLUSIONS CT perfusion imaging is a valuable technique for the diagnosis of pulmonary nodules. Lung cancer had higher perfusion and permeability than benign lesions. The evidence suggests blood volume is the best surrogate marker for characterizing the blood supply, while permeability surface has a high specificity in quantifying the vascular permeability.


Assuntos
Neoplasias Pulmonares/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , China , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Perfusão , Imagem de Perfusão/métodos , Viés de Publicação , Sensibilidade e Especificidade
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