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1.
Auris Nasus Larynx ; 50(6): 874-879, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37076340

RESUMO

OBJECTIVE: Cochlear implants (CIs) were noncompatible with magnetic resonance imaging (MRI) initially; however, recently, implants have become available that are compatible with MRI without the need for magnet removal or bandage fixation. The images produced by MRI scans are sometimes deteriorated by artifacts and are not clinically useful. In this study, we discussed the size differences of such artifacts with respect to the imaging modality and sequences with their clinical validity. METHODS: We performed a head MRI, using a head bandage and without magnet removal in five patients who underwent cochlear implantation at our department and analyzed the MRI findings. RESULTS: Without magnet removal, diffusion-weighted images and T2 star-weighted images had larger artifacts and less useful images. T1-weighted images, T2-weighted images (T2WIs), T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) images, and heavy T2WIs could evaluate the unimplanted side and middle of the head but had limited applicability on the CI side. CONCLUSION: The characteristic features of MRI scan images vary with the method used as well as with the sequence, suggesting that the choice of MRI is largely determined on the basis of clinical feasibility and the requirement. Accordingly, we need to judge well in advance of imaging whether the images would be clinically relevant.


Assuntos
Implante Coclear , Implantes Cocleares , Humanos , Estudos de Viabilidade , Imageamento por Ressonância Magnética/métodos
2.
Invest Radiol ; 58(6): 373-379, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728880

RESUMO

OBJECTIVES: The aim of this study was to evaluate the usefulness of breath-hold turbo spin echo with deep learning-based reconstruction (BH-DL-TSE) in acquiring fat-suppressed T2-weighted images (FS-T2WI) of the liver by comparing this method with conventional free-breathing turbo spin echo (FB-TSE) and breath-hold half Fourier single-shot turbo spin echo with deep learning-based reconstruction (BH-DL-HASTE). MATERIALS AND METHODS: The study cohort comprised 111 patients with suspected liver disease who underwent 3 T magnetic resonance imaging. Fifty-eight focal solid liver lesions ≥10 mm were also evaluated. Three sets of FS-T2WI were acquired using FB-TSE, prototypical BH-DL-TSE, and prototypical BH-DL-HASTE, respectively. In the qualitative analysis, 2 radiologists evaluated the image quality using a 5-point scale. In the quantitative analysis, we calculated the lesion-to-liver signal intensity ratio (LEL-SIR). Friedman test and Dunn multiple comparison test were performed to assess differences among 3 types of FS-T2WI with respect to image quality and LEL-SIR. RESULTS: The mean acquisition time was 4 minutes and 43 seconds ± 1 minute and 21 seconds (95% confidence interval, 4 minutes and 28 seconds to 4 minutes and 58 seconds) for FB-TSE, 40 seconds for BH-DL-TSE, and 20 seconds for BH-DL-HASTE. In the qualitative analysis, BH-DL-HASTE resulted in the fewest respiratory motion artifacts ( P < 0.0001). BH-DL-TSE and FB-TSE exhibited significantly less motion-related signal loss and clearer intrahepatic vessels than BH-DL-HASTE ( P < 0.0001). Regarding the edge sharpness of the left lobe, BH-DL-HASTE scored the highest ( P < 0.0001), and BH-DL-TSE scored higher than FB-TSE ( P = 0.0290). There were no significant differences among 3 types of FS-T2WI with respect to the edge sharpness of the right lobe ( P = 0.1290), lesion conspicuity ( P = 0.5292), and LEL-SIR ( P = 0.6026). CONCLUSIONS: BH-DL-TSE provides a shorter acquisition time and comparable or better image quality than FB-TSE, and could replace FB-TSE in acquiring FS-T2WI of the liver. BH-DL-TSE and BH-DL-HASTE have their own advantages and may be used complementarily.


Assuntos
Aprendizado Profundo , Doenças do Sistema Digestório , Hepatopatias , Humanos , Hepatopatias/diagnóstico por imagem , Abdome , Respiração , Imageamento por Ressonância Magnética/métodos , Artefatos
3.
Magn Reson Med Sci ; 22(4): 477-485, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36002311

RESUMO

PURPOSE: The optimal temporal resolution for free-breathing dynamic contrast-enhanced MRI (FBDCE-MRI) of the pancreas has not been determined. This study aimed to evaluate the appropriate temporal resolution to achieve good image quality and to perform pharmacokinetic analysis in FBDCE-MRI of the pancreas using golden-angle radial sparse parallel (GRASP). METHODS: Sixteen participants (53 ± 15 years, eight females) undergoing FBDCE-MRI were included in this prospective study. Images were retrospectively reconstructed at four temporal resolutions (1.8, 3.0, 4.8, and 7.8s). Two radiologists (5 years of experience) evaluated the image quality of each reconstructed image by assessing the visualization of the celiac artery (CEA), the common hepatic artery, the splenic artery, each area of the pancreas, and artifacts using a 5-point scale. Using Tissue-4D, pharmacokinetic parameters were calculated for each area in the reconstructed images at each temporal resolution for 16 examinations, excluding two with errors in the pharmacokinetic modeling analysis. Friedman and Bonferroni tests were used for analysis. A P value < 0.05 was considered statistically significant. RESULTS: During vascular assessment, only scores for the CEA at 7.8s were significantly lower than the other temporal resolutions. Scores of all pancreatic regions and artifacts were significantly lower at 1.8s than at 4.8s and 7.8s. In the pharmacokinetic analysis, all volume transfer coefficients (Ktrans), rate constants (Kep), and the initial area under the concentration curve (iAUC) in the pancreatic head and tail were significantly lower at 4.8s and 7.8s than at 1.8s. iAUC in the pancreatic body and extracellular extravascular volume fraction (Ve) in the pancreatic head were significantly lower at 7.8s than at 1.8s. CONCLUSION: A temporal resolution of 3.0s is appropriate to achieve image quality and perform pharmacokinetic analysis in FBDCE-MRI of the pancreas using GRASP.


Assuntos
Meios de Contraste , Aumento da Imagem , Feminino , Humanos , Aumento da Imagem/métodos , Meios de Contraste/farmacocinética , Estudos Retrospectivos , Estudos Prospectivos , Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem
4.
Eur J Radiol ; 136: 109515, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33429209

RESUMO

PURPOSE: To compare the quality of images obtained by T1-weighted hepatobiliary MR cholangiography using Gd-EOB-DTPA with 1-mm isovoxel acquisition and compressed sensing (T1-MRCCS) or parallel imaging (T1-MRCPI) for assessment of biliary tree anatomy. METHOD: We prospectively reviewed T1-MRCCS, T1-MRCPI, and respiratory-triggered 3D T2-weighted MR cholangiography (T2-MRC) images in 58 patients. Two radiologists independently assessed the three sets of images and scored the biliary tree visualization and overall image quality in all cases using a 5-point Likert scale. The resulting scores were compared among T1-MRCCS, T1-MRCPI, and T2-MRC images using a Friedman test followed by a Scheffe test. The inter-reader agreement in scoring was assessed using κ statistics. RESULTS: The image quality scores for the gallbladder on both T1-MRCCS and T1-MRCPI were significantly lower than those on T2-MRC (p < 0.01) for both readers. Meanwhile, the image quality scores for the right and left hepatic ducts and the anterior and posterior branches of the right hepatic duct on both T1-MRCCS and T1-MRCPI were significantly higher than those on T2-MRC (p < 0.05) for both readers. For Reader 2, the overall image quality scores on T1-MRCCS and T1-MRCPI were both significantly higher than those on T2-MRC (p < 0.05). There were no significant differences between the image quality scores on T1-MRCCS and T1-MRCPI for visualization of each bile duct (p < 0.05). CONCLUSIONS: There may be no significant difference in quality between T1-MRCCS images and T1-MRCPI images for assessment of biliary tree anatomy, and both types of images may be better than T2-MRC images, although clinical indication is limited compared with T2-MRC.


Assuntos
Sistema Biliar , Meios de Contraste , Sistema Biliar/diagnóstico por imagem , Colangiografia , Colangiopancreatografia por Ressonância Magnética , Gadolínio DTPA , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
5.
Eur J Radiol ; 122: 108765, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31830630

RESUMO

PURPOSE: To clarify the clinical usefulness of breath-hold compressed sensing three-dimensional magnetic resonance cholangiopancreatography (BH-MRCP) added to conventional respiratory-gating MRCP (RG-MRCP), we prospectively evaluated the image quality of BH-MRCP and compared it with that of RG-MRCP. We also evaluated to what extent the overall image quality was improved by adding BH-MRCP to RG-MRCP. MATERIALS AND METHODS: A total of 113 patients who underwent RG-MRCP and BH-MRCP at a 3-T MR unit were enrolled. We set a scan time of approximately 180 s for RG-MRCP and 20 s for BH-MRCP before examination, and measured actual scan time and assessed image quality using a 5-point scale (5, good; 1, poor). Image quality scores of 1, 2 and 3 were considered clinically inadequate. Image quality scores of RG-MRCP and BH-MRCP were compared. In addition, we compared "RG-MRCP alone" and "hybrid MRCP" (the best-scoring image was picked from RG-MRCP and BH-MRCP when the RG-MRCP score was clinically inadequate). RESULTS: The mean actual scan time of RG-MRCP/BH-MRCP was 191/20 s. The mean scores of RG-MRCP, BH-MRCP and hybrid MRCP were 3.67, 3.35 and 3.92, respectively. The score of hybrid MRCP was significantly better than that of RG-MRCP (P <  0.05). The image quality of RG-MRCP was clinically inadequate in 43/113 (38 %) cases and the inadequate image quality was improved to be clinically adequate in 13/43 (30 %) cases by adding BH-MRCP. CONCLUSION: BH-MRCP brings added value to RG-MRCP because an additional examination of BH-MRCP could compensate for the image deterioration of RG-MRCP caused by motion artifacts.


Assuntos
Suspensão da Respiração , Colangiopancreatografia por Ressonância Magnética/métodos , Pancreatopatias/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Feminino , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Pressão , Adulto Jovem
6.
Jpn J Radiol ; 36(4): 295-302, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29327116

RESUMO

PURPOSE: To compare the visualization of hemodynamic imaging findings of hypervascular hepatocellular carcinoma (HCC) on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) using radial volumetric imaging breath-hold examination with k-space-weighted image contrast reconstruction (r-VIBE-KWIC) versus dynamic computed tomography during hepatic arteriography (dyn-CTHA). MATERIALS AND METHODS: We retrospectively reviewed the databases of preoperative DCE-MRI using r-VIBE-KWIC, dyn-CTHA, and postoperative pathology of resected specimens. Fourteen patients with 14 hypervascular HCCs underwent both DCE-MRI and dyn-CTHA. The imaging findings of the tumor and adjacent liver parenchyma were assessed on both modalities by two readers. The tumor enhancement time was also compared between the two modalities. RESULTS: On DCE-MRI/dyn-CTHA, early staining, peritumoral low-intensity or low-density bands, corona enhancement, and washout of HCC were observed in 14/14 (100%), 10/12 (83%), 11/14 (78%), and 4/14 (29%) patients, respectively. Pathologically, four HCCs with low-density bands on dyn-CTHA had no fibrous capsules. The median tumor enhancement time on DCE-MRI and dyn-CTHA was 24 (9-24) and 23 (8-35) s, respectively. The correlation coefficient between the two groups was 0.762 (P < 0.002). CONCLUSIONS: DCE-MRI using r-VIBE-KWIC has diagnostic potential comparable with that of dyn-CTHA in the hemodynamic evaluation of hypervascular HCC except for the washout phenomenon.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste , Hemodinâmica/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/fisiopatologia , Idoso , Suspensão da Respiração , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/fisiopatologia , Feminino , Humanos , Aumento da Imagem/métodos , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/fisiopatologia , Masculino , Neovascularização Patológica/diagnóstico por imagem , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Eur Radiol ; 26(8): 2790-7, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26601972

RESUMO

OBJECTIVES: To investigate the superiority of radial volumetric breath-hold examination (r-VIBE) with k-space weighted image contrast reconstruction (KWIC) over Cartesian VIBE (c-VIBE) for reducing motion artefacts. METHODS: We acquired r-VIBE-KWIC and c-VIBE images in 10 healthy volunteers. Each acquisition lasted 24 seconds. The volunteers held their breath for decreasing lengths of time during the acquisitions, from 24 to 0 seconds (protocols A-E). Magnetic resonance images at the level of the right portal vein and confluence of hepatic veins were assessed by two readers using a five-point scale with a higher number indicating a better study. RESULTS: The mean scores for the complete r-VIBE-KWIC series (r-VIBEfull) and first r-VIBE-KWIC series (r-VIBE1) were not significantly lower than those for c-VIBE in any protocols. The mean scores for c-VIBE were lower than those for r-VIBEfull and r-VIBE1 in protocols C and D. The mean score for c-VIBE was lower than that for r-VIBEfull in protocol E. The mean score for the eighth r-VIBE-KWIC series (r-VIBE8) was lower than that for c-VIBE only in protocol B. CONCLUSION: r-VIBE-KWIC minimised artefacts relative to c-VIBE at any slice location. The r-VIBE-KWIC's sub-frame images during the breath-holding period were hardly affected by another failed breath-holding period. KEY POINTS: • A two-reader study revealed r-VIBE-KWIC's advantages over c-VIBE • The image quality of r-VIBE-KWIC's sub-frame images was maintained during breath holding • Full-frame r-VIBE-KWIC images minimized motion artefacts caused by breathing • A complete breath holding over half the acquisition time is recommended for c-VIBE • c-VIBE was susceptible to respiratory motion especially in the subphrenic region.


Assuntos
Artefatos , Veias Hepáticas/diagnóstico por imagem , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Veia Porta/diagnóstico por imagem , Adulto , Suspensão da Respiração , Meios de Contraste/farmacologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade
8.
Eur Radiol ; 24(6): 1290-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24633374

RESUMO

OBJECTIVES: To compare radial volumetric imaging breath-hold examination with k-space weighted image contrast reconstruction (r-VIBE-KWIC) to Cartesian VIBE (c-VIBE) in arterial phase dynamic gadoxetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (DCE-MRI) of the liver. METHODS: We reviewed 53 consecutive DCE-MRI studies performed on a 3-T unit using c-VIBE and 53 consecutive cases performed using r-VIBE-KWIC with full-frame image subset (r-VIBEfull) and sub-frame image subsets (r-VIBEsub; temporal resolution, 2.5-3 s). All arterial phase images were scored by two readers on: (1) contrast-enhancement ratio (CER) in the abdominal aorta; (2) scan timing; (3) artefacts; (4) visualisation of the common, right, and left hepatic arteries. RESULTS: Mean abdominal aortic CERs for c-VIBE, r-VIBEfull, and r-VIBEsub were 3.2, 4.3 and 6.5, respectively. There were significant differences between each group (P < 0.0001). The mean score for c-VIBE was significantly lower than that for r-VIBEfull and r-VIBEsub in all factors except for visualisation of the common hepatic artery (P < 0.05). The mean score of all factors except for scan timing for r-VIBEsub was not significantly different from that for r-VIBEfull. CONCLUSIONS: Radial VIBE-KWIC provides higher image quality than c-VIBE, and r-VIBEsub features high temporal resolution without image degradation in arterial phase DCE-MRI. KEY POINTS: Radial VIBE-KWIC minimised artefact and produced high-quality and high-temporal-resolution images. Maximum abdominal aortic enhancement was observed on sub-frame images of r-VIBE-KWIC. Using r-VIBE-KWIC, optimal arterial phase images were obtained in over 90 %. Using r-VIBE-KWIC, visualisation of the hepatic arteries was improved. A two-reader study revealed r-VIBE-KWIC's advantages over Cartesian VIBE.


Assuntos
Gadolínio DTPA , Hepatopatias/patologia , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/patologia , Artefatos , Suspensão da Respiração , Meios de Contraste , Bases de Dados Factuais , Feminino , Artéria Hepática/patologia , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador , Fígado/irrigação sanguínea , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Estudos Retrospectivos
9.
Artigo em Inglês | MEDLINE | ID: mdl-23082592

RESUMO

Typhoid fever is a major health problem in many developing countries and its clinical features are similar to other types of bacterial enterocolitis. Definitive diagnosis by blood culture requires several days and is often unfeasible to perform in developing countries. More efficient and rapid diagnostic methods for typhoid are needed. We compared the pathological changes in the bowel and adjacent tissues of patients having typhoid fever with those having bacterial enterocolitis using ultrasonography. A characteristic of patients with non-typhoidal Salmonella and Campylobacter jejuni enterocolitis was mural thickening of the terminal ileum; only mild mural swelling or no swelling was observed in patients with typhoid fever. Mesenteric lymph nodes in patients with typhoid fever were significantly more enlarged compared to patients with other types of bacterial enterocolitis. Our findings suggest typhoid fever is not fundamentally an enteric disease but rather resembles mesenteric lymphadenopathy and ultrasound is a promising modality for diagnosing typhoid fever in developing countries.


Assuntos
Febre Tifoide/diagnóstico por imagem , Adolescente , Infecções por Campylobacter/diagnóstico por imagem , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni , Criança , Pré-Escolar , Enterocolite/diagnóstico por imagem , Enterocolite/epidemiologia , Enterocolite/microbiologia , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Infecções por Salmonella/diagnóstico por imagem , Infecções por Salmonella/epidemiologia , Febre Tifoide/epidemiologia , Ultrassonografia , Adulto Jovem
10.
Anticancer Res ; 30(6): 1947-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20651338

RESUMO

BACKGROUND: Malignant mesotheliomas reportedly secrete interleukin-6 (IL-6) which augments production of vascular endothelial growth factor (VEGF) from mesothelioma cells. We previously reported the development of a new receptor inhibitor of IL-6 (NRI) by genetically engineering tocilizumab, a humanized anti-IL-6 receptor monoclonal antibody. Since NRI is encoded on a single gene, it is easily applicable to a gene delivery system using virus vehicles. In this study, we report VEGF targeting through NRI expression based on adenovirus-mediated gene delivery in mesothelioma cells. MATERIALS AND METHODS: We constructed an NRI expression vector in the context of a tropism-modified adenovirus vector that had enhanced infectivity in mesothelioma cells. RESULTS: This virus effectively induced NRI secretion from mesothelioma cells. This virus infection also reduced the VEGF production in mesothelioma cells. CONCLUSION: These results indicate that NRI shows potential as an agent in the treatment of mesotheliomas.


Assuntos
Adenoviridae/genética , Anticorpos Monoclonais/uso terapêutico , Terapia Genética , Mesotelioma/terapia , Receptores de Interleucina-6/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Anticorpos Monoclonais/genética , Anticorpos Monoclonais Humanizados , Linhagem Celular Tumoral , Vetores Genéticos , Humanos , Imunoglobulina G/genética , Anticorpos de Cadeia Única/genética , Fator A de Crescimento do Endotélio Vascular/biossíntese
11.
Cells Tissues Organs ; 191(3): 248-59, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19776548

RESUMO

Distribution and total number of myonuclei in single soleus muscle fibers, sampled from tendon to tendon, were analyzed in mdx and wild-type (WT) mice. Apoptotic myonuclei and the microscopic structure around the myonuclei were also analyzed. Three types of muscle fibers of mdx mice with myonuclear distribution at either central, peripheral, or both central and peripheral regions were observed in the longitudinal analyses. All of the myonuclei were located at the peripheral region in WT mice. The total number of myonuclei counted in the whole length of fibers with peripheral myonuclei only was 17% less in mdx than in WT mice (p < 0.05). But the total myonuclear numbers in mdx mouse fibers with different distribution (peripheral vs. central) of myonuclei were identical, and the peripheral nucleus was noted where the central nucleus was missing. Myonuclei located between the center and peripheral regions were also seen in the cross-sectional analyses of muscle fibers. The cross-sectional area and length of fibers, sarcomere number, myonuclear size, myosin heavy chain expression, satellite cell number and neuromuscular junction were identical between each type of fiber. Apoptosis was not detected in any myonuclei located either in central or peripheral regions of muscle fibers. Thus, it was suggested that apoptosis-related loss of central myonuclei and regeneration-related new accretion at the peripheral region is not the cause of different distribution of myonuclei seen in muscle fibers in mdx mice. However, it was speculated that cross-sectional migration of myonuclei from central to peripheral regions may be induced in response to regeneration, because the total myonuclear numbers in fibers with different distribution of myonuclei were identical, and the peripheral nucleus was noted where the central nucleus was missing. Further, myonuclei located between the center and peripheral regions were also seen. However, the question remains as to how or why nuclei might migrate to the periphery in a regenerating muscle fiber, since there was no microscopic evidence of any structural changes around the myonuclei that may be responsible for the movement of the nucleus.


Assuntos
Núcleo Celular , Distrofina , Fibras Musculares Esqueléticas/patologia , Animais , Apoptose , Núcleo Celular/patologia , Núcleo Celular/ultraestrutura , Distrofina/deficiência , Distrofina/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos mdx , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Fibras Musculares Esqueléticas/fisiologia , Fibras Musculares Esqueléticas/ultraestrutura , Distrofia Muscular de Duchenne/metabolismo , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/fisiopatologia , Junção Neuromuscular/patologia , Junção Neuromuscular/ultraestrutura , Regeneração , Células Satélites de Músculo Esquelético/patologia , Células Satélites de Músculo Esquelético/ultraestrutura
12.
Am J Physiol Renal Physiol ; 297(3): F679-84, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19570877

RESUMO

Hyperlipidemia has been demonstrated to be associated with renal disease, yet the mechanism of renal injury is still poorly understood. Inflammation that occurs with the hyperlipidemia has been considered to play an important role in development of glomerular injury. In the present study, we investigated the role of interleukin-6 (IL-6), a key inflammatory molecule, on renal injury in apolipoprotein E-deficient (ApoE(-/-)) mice with severe hypercholesterolemia. The 6-wk-old mice were fed a high-fat diet and administered weekly rat anti-IL-6 receptor monoclonal antibody (MR16-1), control rat IgG, or saline for a total of 4 wk. We examined histopathological changes in the kidney and urinary excretion of protein and albumin. Saline- and IgG-treated mice showed remarkable proteinuria at 10 wk of age, whereas MR16-1-treated mice exhibited significantly lower levels. Renal histopathology of saline- and IgG-treated mice revealed striking lipid deposits and foam cells in the glomerular tuft, juxtaglomerular area, and arteriolar wall along with range of mesangial cell proliferation and matrix expansion. Notably, the severity of lipid deposits and mesangial cell proliferation were significantly reduced in MR16-1-treated mice. Immunohistochemistry demonstrated that mesangial IL-6 expression was dramatically reduced in MR16-1-treated mice compared with IgG-treated mice. Blocking the IL-6 receptor prevented progression of proteinuria and renal lipid deposit, as well as the mesangial cell proliferation associated with severe hyperlipoproteinemia. These results clearly demonstrate that IL-6 plays an essential role in the pathogenesis of hyperlipidemia-induced glomerular injury in ApoE(-/-) mice and suggests the usefulness of anti-IL-6 receptor antibody in treatments for hyperlipidemia-induced organ damage.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Apolipoproteínas E/deficiência , Glomerulonefrite/prevenção & controle , Hipercolesterolemia/terapia , Interleucina-6/metabolismo , Rim/imunologia , Receptores de Interleucina-6/antagonistas & inibidores , Albuminúria/imunologia , Albuminúria/prevenção & controle , Animais , Apolipoproteínas E/genética , Pressão Sanguínea , Proliferação de Células , Modelos Animais de Doenças , Glomerulonefrite/imunologia , Glomerulonefrite/fisiopatologia , Frequência Cardíaca , Hipercolesterolemia/complicações , Hipercolesterolemia/imunologia , Hipercolesterolemia/fisiopatologia , Rim/patologia , Masculino , Células Mesangiais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos , Receptores de Interleucina-6/metabolismo , Índice de Gravidade de Doença
13.
Arthritis Res Ther ; 11(1): R1, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19121222

RESUMO

INTRODUCTION: Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease characterized by various clinical manifestations. Several cytokines interact and play pathological roles in SLE, although the etiopathology is still obscure. In the present study we investigated the network of immune response-related molecules expressed in the peripheral blood of SLE patients, and the effects of cytokine interactions on the regulation of these molecules. METHODS: Gene expression profiles of peripheral blood from SLE patients and from healthy women were analyzed using DNA microarray analysis. Differentially expressed genes classified into the immune response category were selected and analyzed using bioinformatics tools. Since interactions among TNF, IFNgamma, beta-estradiol (E2), and IFNalpha may regulate the expression of interferon-inducible (IFI) genes, stimulating and co-stimulating experiments were carried out on peripheral blood mononuclear cells followed by analysis using quantitative RT-PCR. RESULTS: Thirty-eight downregulated genes and 68 upregulated genes were identified in the functional category of immune response. Overexpressed IFI genes were confirmed in SLE patient peripheral bloods. Using network-based analysis on these genes, several networks including cytokines--such as TNF and IFNgamma--and E2 were constructed. TNF-regulated genes were dominant in these networks, but in vitro TNF stimulation on peripheral blood mononuclear cells showed no differences in the above gene expressions between SLE and healthy individuals. Co-stimulating with IFNalpha and one of TNF, IFNgamma, or E2 revealed that TNF has repressive effects while IFNgamma essentially has synergistic effects on IFI gene expressions in vitro. E2 showed variable effects on IFI gene expressions among three individuals. CONCLUSIONS: TNF may repress the abnormal regulation by IFNalpha in SLE while IFNgamma may have a synergistic effect. Interactions between IFNalpha and one of TNF, IFNgamma, or E2 appear to be involved in the pathogenesis of SLE.


Assuntos
Estradiol/metabolismo , Regulação da Expressão Gênica/imunologia , Interferon Tipo I/metabolismo , Interferon gama/metabolismo , Lúpus Eritematoso Sistêmico/genética , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/imunologia , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
Curr Gene Ther ; 8(4): 247-55, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18691020

RESUMO

Prognosis of multiple myeloma (MM) remains insufficient despite the intervention of high dose chemotherapy with auto- or allo- hematopoietic stem cell transplantation and the advent of molecular target drugs such as thalidomide, lenalidomide, and bortezomib. Further development or new concepts of therapeutic approaches are still required for MM treatment. Current standard protocol for MM treatment does not include gene delivery method or oncolytic virus approaches. Since MM is a disorder originated from B cell lineage, it involves immunological aspects in both pathogenesis and clinical manifestations. Therefore, the comprehension of immunology as well as oncology is essential to exploit new therapeutic approaches. Recently, novel therapeutic concepts for MM have been emerging. In this review, we present current progress of gene therapy related to MM treatments as well as the overview of MM treatment history.


Assuntos
Citocinas/uso terapêutico , Terapia Genética , Vetores Genéticos/uso terapêutico , Mieloma Múltiplo/terapia , Animais , Citocinas/genética , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/virologia , Terapia Viral Oncolítica
15.
J Immunol ; 180(12): 8126-34, 2008 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-18523277

RESUMO

Previously, we showed that nasal administration of a naked cDNA plasmid expressing Flt3 ligand (FL) cDNA (pFL) enhanced CD4(+) Th2-type, cytokine-mediated mucosal immunity and increased lymphoid-type dendritic cell (DC) numbers. In this study, we investigated whether targeting nasopharyngeal-associated lymphoreticular tissue (NALT) DCs by a different delivery mode of FL, i.e., an adenovirus (Ad) serotype 5 vector expressing FL (Ad-FL), would provide Ag-specific humoral and cell-mediated mucosal immunity. Nasal immunization of mice with OVA plus Ad-FL as mucosal adjuvant elicited high levels of OVA-specific Ab responses in external secretions and plasma as well as significant levels of OVA-specific CD4(+) T cell proliferative responses and OVA-induced IFN-gamma and IL-4 production in NALT, cervical lymph nodes, and spleen. We also observed higher levels of OVA-specific CTL responses in the spleen and cervical lymph nodes of mice given nasal OVA plus Ad-FL than in mice receiving OVA plus control Ad. Notably, the number of CD11b(+)CD11c(+) DCs expressing high levels of costimulatory molecules was preferentially increased. These DCs migrated from the NALT to mucosal effector lymphoid tissues. Taken together, these results suggest that the use of Ad-FL as a nasal adjuvant preferentially induces mature-type NALT CD11b(+)CD11c(+) DCs that migrate to effector sites for subsequent CD4(+) Th1- and Th2-type cytokine-mediated, Ag-specific Ab and CTL responses.


Assuntos
Adenoviridae/genética , Movimento Celular/imunologia , Células Dendríticas/imunologia , Tecido Linfoide/imunologia , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Sistema Fagocitário Mononuclear/imunologia , Nasofaringe/imunologia , Adjuvantes Imunológicos/genética , Administração Intranasal , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/genética , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Células Dendríticas/virologia , Feminino , Vetores Genéticos/administração & dosagem , Humanos , Imunidade nas Mucosas/genética , Tecido Linfoide/citologia , Tecido Linfoide/virologia , Proteínas de Membrana/administração & dosagem , Camundongos , Camundongos Endogâmicos C57BL , Sistema Fagocitário Mononuclear/citologia , Sistema Fagocitário Mononuclear/virologia , Nasofaringe/citologia , Nasofaringe/virologia , Tirosina Quinase 3 Semelhante a fms/metabolismo
16.
Curr Pharm Des ; 14(12): 1217-24, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18473869

RESUMO

After three decades from the development of the hybridoma technology, a monoclonal antibody-based therapy targeting the inflammatory cytokine has been established as an ultimate treatment for chronic inflammatory diseases. Interleukine-6 (IL-6) is one of the inflammatory cytokines playing a pivotal role in these conditions, and strategies targeting IL-6 signal show promise in the treatment of chronic inflammatory diseases such as rheumatoid arthritis, juvenile idiopathic arthritis, and Crohn's disease. Although many groups have been exploring the approach to block the IL-6 signal, tocilizumab, a humanized monoclonal antibody of the IL-6 receptor, has been the most intensively studied agent for clinical use. Clinical trials regarding chronic inflammatory diseases described above have demonstrated efficacy of tocilizumab, however, this treatment has limitations in terms of economic costs and ease of administration, and further advances are necessary to expand the concept of IL-6-specific therapeutics. In this review, we discuss targeting IL-6 in a rational drug design and present the various strategies to achieve this.


Assuntos
Interleucina-6/antagonistas & inibidores , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Hiperplasia do Linfonodo Gigante/tratamento farmacológico , Hiperplasia do Linfonodo Gigante/imunologia , Doença de Crohn/tratamento farmacológico , Doença de Crohn/imunologia , Desenho de Fármacos , Técnicas de Transferência de Genes , Humanos , Interleucina-6/química , Interleucina-6/imunologia , Mieloma Múltiplo/tratamento farmacológico , Peptídeos/genética , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Conformação Proteica , Receptores de Interleucina-6/química , Receptores de Interleucina-6/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Transdução de Sinais
17.
Cancer Res ; 67(3): 871-5, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17283116

RESUMO

Interleukin-6 (IL-6) is a key molecule involved in the pathogenesis of several inflammatory diseases and malignancies. Treatments that inhibit IL-6 mitigate the clinical conditions of such diseases. Here, we report on the development of a new receptor inhibitor of IL-6 (NRI) by genetically engineering tocilizumab, a humanized anti-IL-6 receptor monoclonal antibody which specifically blocks IL-6 signaling. This NRI consists of VH and VL of tocilizumab in a single-chain fragment format dimerized by fusing to the Fc portion of human immunoglobulin G(1). The binding activity to IL-6 receptor and the biological activity of the purified NRI were found to be similar to those of parental tocilizumab. Because NRI is encoded on a single gene, it is easily applicable to a gene delivery system using virus vehicles. We administered an adenovirus vector encoding NRI to mouse i.p. and monitored the serum NRI level and growth reduction property on S6B45, an IL-6-dependent multiple myeloma cell line, in vivo. Adequate amount of the serum NRI level to exert anti-IL-6 action could be obtained by the NRI gene introduction combined with adenovirus gene delivery, and this treatment inhibited the in vivo S6B45 cell growth significantly. These findings indicate that NRI is a promising agent applicable to the therapeutic gene delivery approach for IL-6-driven diseases.


Assuntos
Anticorpos Monoclonais/genética , Terapia Genética/métodos , Interleucina-6/fisiologia , Mieloma Múltiplo/terapia , Receptores de Interleucina-6/antagonistas & inibidores , Adenoviridae/genética , Animais , Anticorpos Monoclonais/sangue , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais Humanizados , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Feminino , Engenharia Genética , Vetores Genéticos/genética , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Interleucina-6/metabolismo , Camundongos , Camundongos SCID , Mieloma Múltiplo/genética , Mieloma Múltiplo/imunologia , Receptores de Interleucina-6/imunologia , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Int J Cancer ; 119(6): 1303-11, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16642474

RESUMO

Malignant mesothelioma (MM), an incurable tumor, is reportedly an interleukin-6 (IL-6) secreting tumor. The pathological significance of IL-6 overexpression in this tumor, however, has remained unclear. We investigated the biological functions of IL-6 in mesotheliomas. Five mesothelioma cell lines were analyzed for IL-6 production and IL-6 receptor (IL-6R) expression. Of them, 2 produced high levels of IL-6, 2 produced intermediate levels and 1 cell line showed no secretion. All mesothelioma cell lines used in this study expressed very small amounts of IL-6R mRNA. We compensated for this low level of IL-6R expression in mesotheliomas by adding recombinant soluble IL-6R (sIL-6R) to mediate the IL-6 signal. IL-6 together with sIL-6R was found to promote cell growth of H2052 and H226 MMs classified as high-level IL-6 producers in a dose-dependent manner. Moreover, a humanized anti-IL-6R antibody (MRA) capable of blocking IL-6 signaling suppressed the cell growth of mesotheliomas induced by IL-6/sIL-6R. These findings demonstrate that IL-6 serves as an autocrine growth factor in the development of mesothelioma. In addition, IL-6/sIL-6R stimulation increased the expression of vascular endothelial growth factor (VEGF) in 4 out of 5 cell lines, and this induction was inhibited by MRA treatment. The involvement of the signal transducer and activator of transcription 3 (STAT3) pathway in both cell growth and VEGF induction by IL-6/sIL-6R was verified by dominant negative STAT3 transduction combined with adenovirus gene-delivery methods. Although IL-6 induces VEGF through the JAK2/STAT3 pathway, anti-VEGF antibody could not inhibit the IL-6-induced cell growth observed in H2052 and H226. We concluded that IL-6-dependent growth does not occur via VEGF induction. These results suggest that treatment with anti-IL-6R antibody may constitute a potential molecular targeting therapy for MMs.


Assuntos
Proliferação de Células , Interleucina-6/farmacologia , Mesotelioma/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor gp130 de Citocina/metabolismo , Humanos , Mesotelioma/tratamento farmacológico , Receptores de Interleucina-6/metabolismo , Fator de Transcrição STAT1 , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas
19.
J Gastroenterol ; 40(1): 31-42, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15692787

RESUMO

BACKGROUND: Gastric cancer is the fourth most common malignancy worldwide. Adenoviral vectors (Ads) have been applied for gene therapy of various cancers because of their high transduction efficiency. However, the infectivity of gastrointestinal cancer cells is poor due to the limited expression of the Coxsackie-adenovirus receptor (CAR). In addition, few tumor-specific promoters (TSPs) have been characterized for this type of cancer. To overcome these problems, we proposed TSP-driven conditionally replicating adenoviruses (CRAds) with fiber modification for virotherapy of gastric cancer. METHODS: We assessed the expression profile of eight TSPs in gastric cancer cell lines and evaluated promising candidates in the context of CRAd cytocidal effect. Next, infectivity enhancement by fiber modifications was analyzed in the gastric cancer cell lines. Finally, we combined the TSP-driven CRAds of choice with the fiber modifications to augment the killing effect. RESULTS: Out of the eight TSPs, the midkine (MK) and cyclooxygenase-2 (Cox-2M and Cox-2L) promoters showed high transcriptional activity in gastric cancer cells. When these promoters were used in a CRAd context, Cox-2 CRAds elicited the strongest cytocidal effect. The greatest infectivity enhancement was observed with adenoviral vectors displaying 5/3 chimeric fibers. Likewise, Cox-2 CRAds with 5/3 chimeric fibers showed the strongest cytocidal effect in gastric cancer cell lines. Therefore, Cox-2 CRAds with 5/3 chimeric fiber modification showed good selectivity and infectivity in gastric cancer cells to yield enhanced oncolysis. CONCLUSIONS: Cox-2 CRAds with 5/3 chimeric fiber modification are promising for virotherapy of gastric cancer.


Assuntos
Elementos Facilitadores Genéticos/genética , Vetores Genéticos/genética , Vetores Genéticos/uso terapêutico , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Adenoviridae/efeitos dos fármacos , Adenoviridae/fisiologia , Linhagem Celular Tumoral , Proteína de Membrana Semelhante a Receptor de Coxsackie e Adenovirus , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Citocinas/efeitos dos fármacos , Citocinas/genética , Elementos Facilitadores Genéticos/efeitos dos fármacos , Peptídeo Liberador de Gastrina/uso terapêutico , Fármacos Gastrointestinais/uso terapêutico , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/genética , Vetores Genéticos/efeitos dos fármacos , Humanos , Integrinas/biossíntese , Integrinas/efeitos dos fármacos , Integrinas/genética , Midkina , Terapia Viral Oncolítica , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Proteínas Secretadas Inibidoras de Proteinases , Proteínas/uso terapêutico , Receptores Virais/biossíntese , Receptores Virais/efeitos dos fármacos , Receptores Virais/genética , Inibidores de Serina Proteinase/uso terapêutico , Neoplasias Gástricas/virologia , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Fator A de Crescimento do Endotélio Vascular/uso terapêutico , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
20.
J Gene Med ; 6(11): 1281-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15368588

RESUMO

BACKGROUND: Gene therapy is a novel approach for treatment of patients with advanced, recurrent, or metastatic cervical cancer. One effective way to direct transgene expression to specific tissues or tumors is the use of tissue-specific-promoters (TSPs). In the context of adenovirus (Ad)-mediated cancer gene therapy it is rational to choose a TSP which is highly expressed in the tumor but has potentially low activity in non-tumor cells, especially the liver. In this study, we have investigated several promoters which fulfill these criteria. Candidate cervical cancer specific TSPs include promoters of the genes for secretory leukoprotease inhibitor (SLPI), cyclooxygenase-2 (COX-2), Midkine (MK), vascular endothelial growth factor receptor type 1 (flt-1), vascular endothelial growth factor (VEGF), Survivin and the receptor for chemokine SDS-1 (CXCR4). METHODS: To evaluate the specific gene expression of the different promoters in the context of cervical cancer, we constructed a panel of E1-deleted Ads that express luciferase under the control of the promoters of interest. We investigated various established cervical cancer cell lines, as well as purified primary cancer cells and normal control cells from the cervix uteri. RESULTS: In all cell lines tested, promoters for MK, VEGF and CXCR4 showed the highest activity. Both MK and VEGF promoters also resulted in a high activity in primary cervical cancer cells. Interestingly, gene expression profiles correlate with luciferase activity in both cell lines and primary cancer samples. CONCLUSIONS: Our study demonstrates that the promoters for MK and VEGF are active in cervical cancer. We believe that both promoters can be successfully employed as TSPs for gene therapy targeted to cervical cancer.


Assuntos
Regiões Promotoras Genéticas , Neoplasias do Colo do Útero/genética , Adenoviridae/genética , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/genética , Citocinas/genética , Proteínas da Matriz Extracelular/genética , Feminino , Humanos , Proteínas Inibidoras de Apoptose , Proteínas Associadas aos Microtúbulos/genética , Midkina , Cadeias Pesadas de Miosina , Proteínas de Neoplasias/genética , Miosina não Muscular Tipo IIB , Proteínas Secretadas Inibidoras de Proteinases , Proteínas/genética , Receptores CXCR4/genética , Inibidor Secretado de Peptidases Leucocitárias , Survivina , Fator A de Crescimento do Endotélio Vascular/genética
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