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This study aims to explore the mechanism of Liujunzi Decoction in the treatment of 4-nitroquinoline-N-oxide(4NQO)-induced esophageal cancer in mice. One hundred mice of 35-45 days were randomized into blank, model, and low-, medium-, and high-concentration(18.2, 36.4, and 54.6 g·kg~(-1), respectively) Liujunzi Decoction groups. The mice in other groups except the blank group had free access to the water containing 100 µg·mL~(-1) 4NQO for 16 weeks for the modeling of esophageal cancer. The mice in the Liujunzi Decoction groups were fed with the diets supplemented with corresponding concentrations of Liujunzi Decoction. The body weight and organ weights were weighed for the calculation of organ indexes. The pathological changes of the esophageal tissue were observed by hematoxylin-eosin(HE) staining. Ultra performance liquid chromatography-mass spectrometry(UPLC-MS/MS) was employed to collect metabolites from mouse serum samples, screen out potential biomarkers, and predict related metabolic pathways. Compared with the blank group, the model group showed decreased spleen and stomach indexes and increased lung, esophagus, and kidney indexes. Compared with the model group, Liujunzi Decoction groups had no significant changes in the organ indexes. The HE staining results showed that Liujunzi Decoction inhibited the invasive growth and cancerization of the esophageal cancer cells. A total of 9 potential biomarkers of Liujunzi Decoction in treating esophageal cancer were screened out in this study, which were urocanic acid, 1-oleoylglycerophosphoserine, 11-deoxy prostaglandin E1, Leu-Glu-Lys-Glu,(±) 4-hydroxy-5E,7Z,10Z,13Z,16Z,19Z-docosahexaenoic acid, ureidosuccinic acid,(2R)-2,4-dihydroxy-3,3-dimethylbutanoic acid, kynurenic acid, and bicyclo prostaglandin E2, which were mainly involved in histidine, pyrimidine, alanine, aspartate, glutamate, pantothenate and tryptophan metabolism and coenzyme A biosynthesis. In summary, Liujunzi Decoction may exert the therapeutic effect on the 4NQO-induced esophageal cancer in mice by regu-lating the amino acid metabolism, inflammation, and immune function.
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Medicamentos de Ervas Chinesas , Neoplasias Esofágicas , Espectrometria de Massas em Tandem , Camundongos , Animais , Cromatografia Líquida , Metabolômica , Biomarcadores , Neoplasias Esofágicas/induzido quimicamente , Neoplasias Esofágicas/tratamento farmacológicoRESUMO
Complex vector modes are opening burgeoning opportunities for a wide variety of applications and therefore the flexible manipulation of their various properties has become a topic of late. As such, in this Letter, we demonstrate a longitudinal spin-orbit separation of complex vector modes propagating in free space. To achieve this, we employed the recently demonstrated circular Airy Gaussian vortex vector (CAGVV) modes, which feature a self-focusing property. More precisely, by properly manipulating the intrinsic parameters of CAGVV modes, the strong coupling between the two constituting orthogonal components can be engineered to undergo a spin-orbit separation along the propagation direction. In other words, while one polarization component focuses at one plane, the other focuses at a different plane. Such spin-orbit separation, which we demonstrated by numerical simulations and corroborated experimentally, can be adjusted on-demand by simply changing the initial parameters of the CAGVV mode. Our findings will be of great relevance in applications such as optical tweezers, to manipulate micro- or nano-particles at two different parallel planes.
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BACKGROUND: Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related death worldwide. Due to the high prevalence of hepatitis B virus (HBV) infection in China, the incidence of HCC in China is high, and liver cirrhosis caused by chronic hepatitis also brings great challenges to treatment. This paper reviewed the latest research progress on minimally invasive treatments for HCC, including percutaneous thermal ablation and new nonthermal ablation techniques, and introduced the principles, advantages, and clinical applications of various therapeutic methods in detail. DATA SOURCES: The data of treatments for HCC were systematically collected from the PubMed, ScienceDirect, American Chemical Society and Web of Science databases published in English, using "minimally invasive" and "hepatocellular carcinoma" or "liver cancer" as the keywords. RESULTS: Percutaneous thermal ablation is still a first-line strategy for the minimally invasive treatment of HCC. The effect of microwave ablation (MWA) on downgrading treatment before liver transplantation is better than that of radiofrequency ablation (RFA), while RFA is more widely used in the clinical practice. High-intensity focused ultrasound (HIFU) is mainly used for the palliative treatment of advanced liver cancer. Electrochemotherapy (ECT) delivers chemotherapeutic drugs to the target cells while reducing the blood supply around HCC. Irreversible electroporation (IRE) uses a microsecond-pulsed electric field that induces apoptosis and necrosis and triggers a systemic immune response. The nanosecond pulsed electric field (nsPEF) has achieved a good response in the ablation of mice with HCC, but it has not been reported in China for the treatment of human HCC. CONCLUSIONS: A variety of minimally invasive treatments provide a sufficient survival advantage for HCC patients. Nonthermal ablation will lead to a new wave with its unique advantage of antitumor recurrence and metastasis.
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Técnicas de Ablação , Carcinoma Hepatocelular , Ablação por Cateter , Neoplasias Hepáticas , Ablação por Radiofrequência , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Técnicas de Ablação/efeitos adversos , Técnicas de Ablação/métodos , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Resultado do TratamentoRESUMO
Stokes polarimetry (SP) is a powerful technique that enables spatial reconstruction of the state of polarization (SoP) of a light beam using only intensity measurements. A given SoP is reconstructed from a set of four Stokes parameters, which are computed through four intensity measurements. Since all intensities must be performed on the same beam, it is common to record each intensity individually, one after the other, limiting its performance to light beams with static SoP. Here, we put forward a novel technique to extend SP to a broader set of light beams with dynamic SoP. This technique relies on the superposition principle, which enables the splitting of the input beam into identical copies, allowing the simultaneous measurement of all intensities. For this, the input beam is passed through a multiplexed digital hologram displayed on a polarization-insensitive Digital Micromirror Device (DMD) that grants independent and rapid (20 kHz) manipulation of each beam. We are able to reliably reconstruct the SoP with high fidelity and at speeds of up to 27 Hz, paving the way for real-time polarimetry of structured light.
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Laser remote sensing represents a powerful tool that enables the accurate measurement of the speed of moving targets. Crucially, most sensing techniques are two-dimensional (2D) and only enable direct determination of the speed along the line of sight. Here we put forward a novel three-dimensional technique that enables the direct and simultaneous measurement of both the longitudinal and angular speed of cooperative targets. This technique is based on the use of complex vector light beams, whose polarization and spatial degree of freedom are coupled in a non-separable way. We present evidence of our technique by performing a proof-of-principle experiment.
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OBJECTIVES: This study aimed to investigate role of Numb in the epithelial mesenchymal transition (EMT) of breast cancer. METHODS: Numb and ß-catenin were inhibited in MCF-7 cells using sh-RNA and overexpressed in T47D cells by pcDNA3.0-Numb, pcDNA3.0-ß-catenin. Cell proliferation, invasion and migration were evaluated using MTT and Transwell assay, respectively. ß-catenin, Lin28, and EMT related markers were determined using qRT-PCR and Western Blotting. RESULTS: Knockdown of Numb significantly promoted the proliferation, invasion and migration of MCF-7 cells, further increased the expression of ß-catenin, Lin28, Snail-1, and N-cadherin, as well as decreased E-cadherin. In T47D cells transfected with pcDNA3.0-Numb, the results were quite the reverse. CONCLUSIONS: Knockdown of Numb could promote the EMT of breast cancer cells via ß-cateni/Lin28 signaling pathway.
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Neoplasias da Mama/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas de Ligação a RNA/metabolismo , beta Catenina/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Células MCF-7 , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Interferência de RNA , Proteínas de Ligação a RNA/genética , Transdução de Sinais/genética , beta Catenina/genéticaRESUMO
LIGHT recruits and activates naive T cells in the islets at the onset of diabetes. IFN-γ secreted by activated T lymphocytes is involved in beta cell apoptosis. However, whether LIGHT sensitizes IFNγ-induced beta cells destruction remains unclear. In this study, we used the murine beta cell line MIN6 and primary islet cells as models for investigating the underlying cellular mechanisms involved in LIGHT/IFNγ - induced pancreatic beta cell destruction. LIGHT and IFN-γ synergistically reduced MIN6 and primary islet cells viability; decreased cell viability was due to apoptosis, as demonstrated by a significant increase in Annexin V(+) cell percentage, detected by flow cytometry. In addition to marked increases in cytochrome c release and NF-κB activation, the combination of LIGHT and IFN-γ caused an obvious decrease in expression of the anti-apoptotic proteins Bcl-2 and Bcl-xL, but an increase in expression of the pro-apoptotic proteins Bak and Bax in MIN6 cells. Accordingly, LIGHT deficiency led to a decrease in NF-κB activation and Bak expression, and peri-insulitis in non-obese diabetes mice. Inhibition of NF-κB activation with the specific NF-κB inhibitor, PDTC (pyrrolidine dithiocarbamate), reversed Bcl-xL down-regulation and Bax up-regulation, and led to a significant increase in LIGHT- and IFN-γ-treated cell viability. Moreover, cleaved caspase-9, -3, and PARP (poly (ADP-ribose) polymerase) were observed after LIGHT and IFN-γ treatment. Pretreatment with caspase inhibitors remarkably attenuated LIGHT- and IFNγ-induced cell apoptosis. Taken together, our results indicate that LIGHT signalling pathway combined with IFN-γ induces beta cells apoptosis via an NF-κB/Bcl2-dependent mitochondrial pathway.
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Apoptose/efeitos dos fármacos , Interferon gama/farmacologia , Mitocôndrias/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/farmacologia , Animais , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Ativação Enzimática/efeitos dos fármacos , Feminino , Células Secretoras de Insulina/metabolismo , Camundongos Endogâmicos NOD , Mitocôndrias/efeitos dos fármacos , Modelos Biológicos , Proteínas Recombinantes de Fusão/metabolismo , Estresse Fisiológico/efeitos dos fármacosRESUMO
Laser micromachining has proven to be a useful tool for precision processing of semiconductors. For Silicon Carbide (SiC) single crystals, ablation with ultraviolet wavelength laser could lead to the maximum absorption efficiency of incident energy. In this paper, laser ablations were performed on 6H-SiC single crystals through a 355 nm solid state laser. Different confining media were also employed to find the optimal processing condition. The surface of SiC after laser ablation was characterized by Raman spectroscopy. Amorphous silicon and nanocrystalline graphite were found to be the main compositions left. For SiC wafers ablation in air, the amorphous silicon exhibited mainly around rather than inside the ablated crater. However, the amorphous silicon showed opposite spatial distribution features for samples processing under liquid. Through analysis of the compositions left on the ablated surface, the ablation mechanism was investigated from another point of view. For liquid confined laser processing,previous studies mainly concentrate on the thickness and viscosity of the liquids, little information has been done on the reducibility of liquids. To investigate the influence of liquid reducibility, the surface morphology and oxygen content of ablation under different confining media were checked by confocal laser scanning microscopy and energy dispersive spectroscopy. Results showed that the reducibility of confining liquid also played a vital role in the ablation process under liquid. Utilizing liquids with deoxidizing ability as confining media will result in a remarkable reduction of surface oxygen content and a more regular morphology.
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OBJECTIVE: To investigate the regulative mechanism of the diterpene phenol extract of Rosmarinus Officinalis (DERO) on the imbalance of collagen metabolism of the lung tissue in pulmonary fibrosis rats. METHODS: Fifty healthy Sprague-Dawley rats were randomly divided into the normal saline group (NS), the bleomycin-induced lung injury group (BLM), the low dose DERO group (at the daily dose of 50 mg/kg), the moderate dose DERO group (at the daily dose of 100 mg/kg), and the high dose DERO group (at the daily dose of 200 mg/kg), 10 in each group (abbreviated as DERO 1, 2, 3, respectively). The pulmonary fibrosis rat model was prepared by disposable intratracheal instillation of bleomycin. DERO was administered by gastrogavage as intervention during the repairing process of lung injury. On the morning of the 29th day, the rats' lung tissue was extracted. The karyocyte number, collagen protein, type I collagen (collagen I) and transforming growth factor-beta type II receptor (TGFbetaR II), Smad4 mRNA expressions were semi-quantitatively determined using tissue microarray, HE staining, collagen fiber dyeing, immunohistochemical assay, and in situ hybridization. Using real-time fluorescent quantification RT-PCR, the mRNA expression of transforming growth factor-beta1 (TGF-beta1) were detected. RESULTS: Compared with the NS group, the collagen deposition of the lung tissue was obvious and the inflammatory infiltration was more severe in the BLM group (P < 0.05, P < 0.01). There was no statistical difference in the aforesaid 4 indices between the DERO1 group and the BLM group (P > 0.05). The collagen deposition and the inflammatory infiltration were obviously alleviated in the DERO2 and DERO3 groups (P < 0.05, P < 0.01). Compared with the NS group, the mRNA expressions of collagen-I, TGF-beta1 R II, Smad4, and TGF-beta1 were obviously up-regulated in the BLM group (P < 0.05, P < 0.01). Compared with the BLM group, the aforesaid four indices were not statistically changed in the DERO1 group (P > 0.05). But the mRNA expressions of collagen-I, TGF-beta1 R II, Smad4, and TGF-beta1 were obviously downregulated in the DERO2 and DERO3 groups (P < 0.05, P < 0.01). But the down-regulation of Smad4 expression was not obvious in the DERO2 and the DERO3 groups (P > 0.05). Compared with the DERO1 group, the mRNA expressions of collagen-I, TGF-beta1, R II, TGFbeta1 were all obviously lower in the DERO2 and the DERO3 groups (P < 0.05). But there was no statistical difference in the aforesaid 4 indices between the DERO2 group and the DERO3 group (P > 0.05). CONCLUSIONS: DERO could regulate imbalanced collagen metabolism of pulmonary fibrosis. It could inhibit excessive deposition of collagen fibers, especially excessive deposition of collagen- I. Its mechanisms might be realized by inhibiting up-regulation of TGF-beta1 and TGFbetaR II mRNA expressions, thus interfering the activation of TGF-beta-Smad signaling pathway on target genes, especially on type I procollagen target gene.
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Diterpenos/farmacologia , Extratos Vegetais/farmacologia , Fibrose Pulmonar/metabolismo , Rosmarinus/química , Fator de Crescimento Transformador beta1/metabolismo , Animais , Colágeno Tipo I/metabolismo , Feminino , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Proteínas Serina-Treonina Quinases/metabolismo , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de SinaisRESUMO
Hydrazide-appended pillar[5]arene derivatives have been synthesized. X-ray crystal structure analysis and (1)H NMR studies revealed that the molecules adopt unique tubular conformations. Inserting the molecules into the lipid membranes of vesicles leads to the transport of water through the channels produced by single molecules, as supported by dynamic light scattering and cryo-SEM experiments. The channels exhibit the transport activity at a very low channel to lipid ratio (0.027 mol %), and a water permeability of 8.6 × 10(-10) cm s(-1) is realized. In addition, like natural water channel proteins, the artificial systems also block the transport of protons.
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Aquaporinas/química , Materiais Biomiméticos/química , Hidrazinas/química , Compostos de Amônio Quaternário/química , Água/metabolismo , Aquaporinas/metabolismo , Materiais Biomiméticos/metabolismo , Calixarenos , Cristalografia por Raios X , Hidrazinas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Molecular , Permeabilidade , Compostos de Amônio Quaternário/metabolismoRESUMO
Complex vector modes represent a general state of light nonseparable in their spatial and polarization degrees of freedom, which have inspired a wide variety of novel applications and phenomena, such as their unexpected propagation behaviour. For example, they can propagate describing periodic polarization transitions, changing from one vector beam to another. Here, we put forward a novel class of vector modes with the capability to experience an abruptly autofocusing behaviour. To achieve such beams, we encode the spatial degree of freedom in the Circular Airy Gaussian vortex (CAGV) beams. We demonstrate the experimental generation of arbitrary CAGV vector beams and evince some of their properties, such as a rotation of intermodal phase. We anticipate that the fascinating properties of theses modes will prompt the development of novel applications associated to their autofocusing behaviour and polarization distribution.
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OBJECTIVE: To elucidate the roles of monocyte chemotactic factors (MCP-1, RANTES and Fractalkine) on the vulnerability of atherosclerotic plaques in patients with stable (SAP) and unstable angina pectoris (UAP). METHODS: Patients with SAP (n = 50) and UAP (n = 50) underwent coronary angiography (CAG) and intravenous ultrasound (IVUS) were included in the study. Monocyte chemotaxis was assayed by the transwell chamber. Concentrations of hs-CRP, MCP-1, RANTES and Fractalkine were measured by Enzyme-linked-immunosorbent assay (ELISA). mRNA expression of MCP-1, RANTES and Fractalkine in the monocytes was detected by RT-PCR. RESULTS: IVUS evidenced soft lipid plaques in 48% UAP patients and in 16% SAP patients (P < 0.05). SAP patients had mainly fibrous and mixed plaques. Plaque burden and vascular remodeling index were significantly higher in UAP patients than in SAP patients (P < 0.01). The averaged number of migrated monocytes in the UAP patients were higher than that in patients with SAP (P < 0.01). Concentration of hs-CRP, MCP-1, RANTES and Fractalkine were significantly higher in UAP patients than those of SAP patients (P < 0.05 or P < 0.01). mRNA expression of MCP-1, RANTES and Fractalkine in patients with UAP was significantly higher than those of SAP patients (P < 0.05). CONCLUSION: Upregulated monocyte chemotactic factors (MCP-1, RANTES and Fractalkine) might promote coronary plaque vulnerability in UAP patients.
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Angina Pectoris/metabolismo , Angina Instável/metabolismo , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Quimiocina CX3CL1/metabolismo , Placa Aterosclerótica/patologia , Angina Pectoris/patologia , Angina Instável/patologia , Angiografia Coronária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genéticaRESUMO
Lined up water molecules: Artificial transmembrane channels from pillar[5]arene monomeric and dimeric derivatives have been prepared. Single-channel conductance measurements and isotope effect experiments under acidic conditions showed selective proton transport through the channels, which were mediated by water wires formed in the pillar[5]arene backbones (see picture).
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Membranas Artificiais , Prótons , Compostos de Amônio Quaternário/química , Água/química , Calixarenos , Cristalografia por Raios X , Modelos MolecularesRESUMO
The acute toxicity of zinc threoninate chelate was assessed. The oral lethal dose 50% (LD(50)) was 2710 mg/kg in female rats and 3160 mg/kg in male rats. Genotoxicity was assessed by Ames test in Salmonella typhimurium strains TA97, TA98, TA100, and TA102, by bone marrow mouse micronucleus test and a sperm abnormality test with mice. Thirty-day repeat dose toxicity study was conducted at oral daily doses of 0, 42, 169, and 675 mg/kg in rats. Teratogenicity was assessed at the same daily dose in pregnant rats by gavage. No significant changes in body weight, food consumption, organ weight, relative organ weight, hematology, blood biochemistry, histopathology, behavior, mortality, sperm abnormality, mutagenicity, and micronucleus formation were observed and no clinical signs or adverse effects were detected. Zinc threoninate chelate had no significant teratogenic effect at a daily dose of 42 mg/kg.
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Quelantes/toxicidade , Treonina/análogos & derivados , Treonina/toxicidade , Zinco/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes para Micronúcleos , Testes de Mutagenicidade , Ratos , Salmonella typhimurium/genética , Espermatozoides/efeitos dos fármacos , Teratogênicos/toxicidadeRESUMO
It is well known that when a laser is reflected from a rough surface or transmitted through a diffusive medium, a speckle pattern will be formed at a given observation plane. An important parameter of speckle is its size, which for the case of homogeneous illumination, well-known relations for its computation have been derived. This is not the case for structured light beams of non-homogeneous intensity and phase distribution. Here, we propose and demonstrate, using Hermite- and Laguerre-Gaussian light modes, that the mean size of the speckle generated by these structured light beams can be measured assuming a homogeneous illumination. We further provide with mathematical expressions that relate the speckle size to the generalised definition of "spot size". To reinforce our assessment, we compare the mean speckle size generated by structured light modes with that generated by wave fronts of constant phase and amplitude and show that in both cases the mean speckle size is almost identical. Our findings reveal a fundamental property of speckle, which will be of great relevance in many speckle-based applications and will pave the way towards the development of novel applications.
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In recent time there has been an increasing amount of interest in developing novel techniques for the generation of complex vector light beams. Amongst these, digital holography stands out as one of the most flexible and versatile with almost unlimited freedom in the generation of scalar and complex vector light fields featuring arbitrary polarisation distributions and spatial profiles. In this manuscript we put forward a novel technique, which relies on the polarisation-insensitive attribute of Digital Micromirror Devices (DMDs). In a prior work where we outlined a new detection scheme based on Stokes projections we alluded to this technique. Here we outline the creation process in full, providing all the details for its experimental implementation. In addition, we fully characterise the performance of such technique, providing a quantitative analysis of the generated modes. To this end, we experimentally reconstruct the transverse polarisation distribution of arbitrary vector modes and compare the ellipticity and flatness of the polarisation ellipses with theoretical predictions. Further, we also generate vector modes with arbitrary degrees of non-separability and determine their degree of concurrence comparing this to theoretical predictions.
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Type 1 diabetes (T1D) results from dysfunction of pancreatic islets ß cells. Recent studies supported that endoplasmic reticulum (ER) stress takes an important role in pancreatic ß cell excessive loss, resulting in T1D. Here, we aimed to review the relationship between ER stress and T1D. Additionally, we also reviewed the potential mechanisms underlying ER stress mediated T1D. Studies have shown that severe ER stress is directly involved in the pancreatic ß cells destruction and pathogenesis of T1D. ER stress plays a key part in pancreatic ß cells and T1D, which will help in developing new effective therapeutics for T1D.
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Diabetes Mellitus Tipo 1/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Células Secretoras de Insulina/metabolismo , Animais , HumanosRESUMO
PURPOSE: To evaluate feasibility and added value of dual-energy computed tomography (CT) in diagnosis of pulmonary embolism (PE). MATERIALS AND METHODS: This institutional animal experimental committee-approved study was performed in accordance with animal care guidelines. Eight New Zealand rabbits underwent standard unenhanced and contrast material-enhanced dual-source CT. Gelatin sponge particles were injected into the pulmonary artery, and rabbits underwent contrast-enhanced dual-source CT pulmonary angiography, from which blood-flow (BF) and fusion images were created. Immediately after dual-source CT, rabbits were sacrificed, their lungs were removed and fixed in 10% formalin, and detailed pathologic determination of location and number of lung lobes with PE was performed. Two rabbits were excluded: One died during the procedure. In the other, the catheter tip was retained in the left inferior pulmonary artery. This caused marked postembolization CT image artifacts in adjacent regions. Six rabbits were included in final analysis. Two radiologists without knowledge of pathologic results evaluated five pulmonary lobes in each rabbit and recorded whether PE was present. Pathologic results served as the reference standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the techniques were calculated. Weighted kappa values were calculated to evaluate agreement between modalities. RESULTS: Pathologic analysis revealed PE in 18 of 30 pulmonary lobes. Conventional CT angiography was used to correctly identify PE in 12 lobes and absence of emboli in 18 lobes, which corresponded to sensitivity, specificity, PPV, and NPV of 67%, 100%, 100%, and 67%, respectively. A kappa value of 0.65 indicated good correlation with pathologic findings. On BF images, segments with an embolic region showed low perfusion compared with segments with a normal pulmonary region. BF images and fused images correctly showed PE in 16 of 18 pulmonary lobes and absence of emboli in 11 of 12 lobes, which corresponded to sensitivity, specificity, PPV, and NPV of 89%, 92%, 94%, and 85%, respectively, in detection of PE. A kappa value of 0.80 indicated good correlation with pathologic findings. CONCLUSION: Dual-source CT can depict normal and abnormal blood perfusion distribution in a rabbit's lung. Abnormal pulmonary blood distribution, as shown at dual-source CT, improves detection of acute PE in rabbits.
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Absorciometria de Fóton/métodos , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Animais , Coelhos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
The purpose of the study was to compare the ability of dual energy CT (DECT) and perfusion scintigraphy (PS) to detect pulmonary embolism (PE) in a rabbit model. Gelfoam (n = 20) or saline (n = 4) was injected into the femoral vein of rabbits. After 2 h, DECT pulmonary angiography (CTPA) was used to create blood flow imaging (BFI) and fusion images. The rabbits then underwent PS. Pathological determination of locations and numbers of lung lobes with PE was recorded. The sensitivity and specificity for BFI, CTPA, fused images and PS were calculated using the pathological results as reference standards. Compared with pathological evaluation, CTPA correctly identified PE in 40 lobes and absence of emboli in 80 lobes, corresponding to a sensitivity and specificity of 100%. BFI and fused images correctly identified PE in 40 lobes and the absence of emboli in 78 lobes, corresponding to a sensitivity and specificity of 100% and 98%, respectively. PS correctly detected 27 lobes with PE and 65 lobes without PE, corresponding to a sensitivity and specificity of 68% and 81%, respectively. BFI, CTPA and fused images derived from a single contrast-enhanced DECT provide a higher diagnostic accuracy of detecting PE than PS in a rabbit model.
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Imagem de Perfusão/métodos , Embolia Pulmonar/diagnóstico , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Cintilografia/métodos , Tomografia Computadorizada por Raios X/métodos , Animais , Coelhos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como AssuntoRESUMO
OBJECTIVE: To explore the expression of intercellular adhesion molecule-1 (ICAM-1) in cultured human alveolar type 2 cells (A549) stimulated by mechanical force in vitro. METHODS: Cells were divided into 3 groups: a tensile stress group, a compressive stress group and a control group. The four-point bending system was used to stimulate A549 cells. The cells were stimulated by tensile stress or compressive stress respectively at the same magnitude of 1000 microstrain for 6 h. Sham cells in control group were not subjected to mechanical loading. The protein level and mRNA level of ICAM-1 were measured by Western blot and RT-PCR. Then an inhibitor was added to further explore the possible mechanism. The cells were divided into a tensile stress+inhibitor group, a compressive stress + inhibitor group and a control group. The cells were pretreated with PD98059, a specific inhibitor of extracellular signal-regulated kinase (ERK) for 60 min, and then stimulated respectively by tensile stress or compressive stress at the same magnitude of 1000 microstrain for 6 h or were not subjected to mechanical loading. ICAM-1 protein and mRNA concentrations were determined by Western blot and RT-PCR, respectively. The data were analyzed by one-way ANOVA and Student-Newman-Keuls were used to compare 2 means. RESULTS: The expression of ICAM-1 protein in the tensile stress group (1.16+/-0.07) or the compressive stress group (1.05+/-0.02) were significantly higher than that of the control group (0.78+/-0.07, F=3.31, P<0.05), and the expression of ICAM-1 mRNA in the tensile stress group (1.42+/-0.05) or the compressive stress group (1.27+/-0.05) were also significantly higher than that of the control group (0.13+/-0.04, F=23.1, P<0.01). After pretreated with PD98059 for 60 min, the expression of ICAM-1 protein in the tensile stress group (1.62+/-0.10) was significantly higher than that of the control group (0.50+/-0.03, q=3.75, P<0.05), while there was no significant difference between the compressive stress group (0.60+/-0.03, q=0.32, P>0.05) and the control group. At the transcription level, the expression of ICAM-1 in the tensile stress group (1.57+/-0.03) was significantly higher than that of the control group (0.35+/-0.29, q=3.51, P<0.05), while there was no significant difference between the compressive stress group (0.46+/-0.03, q=0.32, P>0.05) and the control group. CONCLUSIONS: Mechanical forces upregulate the expression of ICAM-1 in A549 cells. PD98059 partly inhibits the upregulation of ICAM-1 induced by mechanical forces. ERK pathway may be partly involved in signal transduction of mechanical force induced expression of ICAM-1 in A549 cells.