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1.
World J Gastrointest Surg ; 16(2): 289-306, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38463362

RESUMO

BACKGROUND: Phospholipase A2 (PLA2) enzymes are pivotal in various biological processes, such as lipid mediator production, membrane remodeling, bioenergetics, and maintaining the body surface barrier. Notably, these enzymes play a significant role in the development of diverse tumors. AIM: To systematically and comprehensively explore the expression of the PLA2 family genes and their potential implications in cholangiocarcinoma (CCA). METHODS: We conducted an analysis of five CCA datasets from The Cancer Genome Atlas and the Gene Expression Omnibus. The study identified differentially expressed genes between tumor tissues and adjacent normal tissues, with a focus on PLA2G2A and PLA2G12B. Gene Set Enrichment Analysis was utilized to pinpoint associated pathways. Moreover, relevant hub genes and microRNAs for PLA2G2A and PLA2G12B were predicted, and their correlation with the prognosis of CCA was evaluated. RESULTS: PLA2G2A and PLA2G12B were discerned as differentially expressed in CCA, manifesting significant variations in expression levels in urine and serum between CCA patients and healthy individuals. Elevated expression of PLA2G2A was correlated with poorer overall survival in CCA patients. Additionally, the study delineated pathways and miRNAs associated with these genes. CONCLUSION: Our findings suggest that PLA2G2A and PLA2G12B may serve as novel potential diagnostic and prognostic markers for CCA. The increased levels of these genes in biological fluids could be employed as non-invasive markers for CCA, and their expression levels are indicative of prognosis, underscoring their potential utility in clinical settings.

2.
Antiviral Res ; 182: 104884, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32750466

RESUMO

Japanese encephalitis virus (JEV), a major cause of Japanese encephalitisis, is an arbovirus that belongs to the genus Flavivirus of the family Flaviviridae. Currently, there is no effective drugs available for the treatment of JEV infection. Therefore, it is important to establish efficient antiviral screening system for the development of antiviral drugs. In this study, we constructed a full-length infectious clone of eGFP-JEV reporter virus by inserting the eGFP gene into the capsid-coding region of the viral genome. The reporter virus RNA transfected-BHK-21 cells generated robust eGFP fluorescence signals that were correlated well with viral replication. The reporter virus displayed growth kinetics similar to wild type (WT) virus although replicated a little slower. Using a known JEV inhibitor, NITD008, we demonstrated that the reporter virus could be used to identify inhibitors against JEV. Furthermore, an eGFP-JEV-based high throughput screening (HTS) assay was established in a 96-well format and used for screening of 1443 FDA-approved drugs. Sixteen hit drugs were identified to be active against JEV. Among them, five compounds which are lonafarnib, cetylpyridinium chlorid, cetrimonium bromide, nitroxoline and hexachlorophene, are newly discovered inhibitors of JEV, providing potential new therapies for treatment of JEV infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/efeitos dos fármacos , Vírus da Encefalite Japonesa (Espécie)/genética , Genes Reporter , Proteínas de Fluorescência Verde/genética , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Cricetinae , Culicidae , Avaliação Pré-Clínica de Medicamentos , Expressão Gênica , Ensaios de Triagem em Larga Escala , Humanos , Rim/citologia , Estados Unidos , United States Food and Drug Administration , Replicação Viral/efeitos dos fármacos
3.
Front Microbiol ; 11: 897, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32582042

RESUMO

Porcine deltacoronavirus (PDCoV) is a novel swine enteropathogenic coronavirus that causes watery diarrhea and induces proinflammatory cytokine responses in piglets. Our previous research showed that the specific-pathogen-free (SPF) chicks exhibited mild diarrhea and low fecal viral shedding, along with cecum lesions after PDCoV infection. Disturbances in the homeostasis of the gut microbiota have been associated with various diseases. We aimed to explore the effects of PDCoV infection on chick gut microbiota, short-chain fatty acid (SCFAs) production, and inflammatory cytokine expression in chicks, and also to investigate the relationship between gut microbiota and SCFAs or inflammatory cytokine expression of the PDCoV-infected chicks. Results obtained using 16S rRNA sequencing showed that infection with PDCoV strain HNZK-02 significantly altered the composition of chick gut microbiota, with the reduced abundance of Eisenbergiella and Anaerotruncus genera at 5 days post-inoculation (dpi) (P < 0.05), and an increased abundance of Alistipes genus at 17 dpi (P < 0.05). The production of SCFAs in the cecum of PDCoV HNZK-02-infected chicks, including acetic acid, propionic acid, and butyric acid, decreased in all cases. The expression of inflammatory cytokines (interferon-γ, tumor necrosis factor-α, and interleukin-10) was increased in the cecum tissue and serum of the PDCoV HNZK-02-infected chicks when detected by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Further analysis showed significant correlation between bacterial genera and SCFAs or inflammatory cytokines expression in cecum of the PDCoV infected chicks. These findings might provide new insight into the pathology and physiology of PDCoV in chicks.

4.
World J Clin Cases ; 7(23): 4063-4074, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31832410

RESUMO

BACKGROUND: Micronodular thymic tumors with lymphoid stroma include micronodular thymoma with lymphoid stroma (MNT) and micronodular thymic carcinoma with lymphoid hyperplasia (MNC), whose micromorphological features are lymphoid stromal hyperplasia and nodular arrangement of tumor epithelial cells. This type of tumor is rare; therefore, the corresponding clinical guidelines, histopathological diagnostic criteria, prognostic factors, and therapeutic regimens have not been established. CASE SUMMARY: This study covers a novel presentation of MNC in a patient and summarizes the clinicopathological characteristics of this type of tumor by using pooled-analysis methods. Morphologically, this tumor type is a series of benign to malignant pedigrees. We establish the following criteria for the classification of micronodular thymic tumors with lymphoid stroma: (1) Tumor cells with moderate-to-severe dysplasia; (2) Tumor cell mitotic figures > 2/10 high-power fields; (3) Appearance of neoplastic necrosis; (4) No terminal deoxynucleotidyl transferase-positive immature T lymphocytes within the tumor; (5) Tumor cells with a Ki-67 index ≥ 10%; and (6) Tumor cells express CD5. Cases that fall into the borders of two categories in terms of morphology are attributed to atypical MNT. It is proposed that the diagnosis of MNT should be established on the diagnostic criteria mentioned above. CONCLUSION: Our diagnostic algorithm can effectively distinguish malignant tumors from benign tumors and provides a potent basis for predicting a prognosis, which offers a practical reference for oncologists and pathologists.

5.
J Virol ; 91(18)2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28659477

RESUMO

West Nile virus (WNV) is a mosquito-borne flavivirus that causes epidemics of encephalitis and viscerotropic disease worldwide. This virus has spread rapidly and has posed a significant public health threat since the outbreak in New York City in 1999. The interferon (IFN)-mediated antiviral response represents an important component of virus-host interactions and plays an essential role in regulating viral replication. Previous studies have suggested that multifunctional nonstructural proteins encoded by flaviviruses antagonize the host IFN response via various means in order to establish efficient viral replication. In this study, we demonstrated that the nonstructural protein 1 (NS1) of WNV antagonizes IFN-ß production, most likely through suppression of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR) activation. In a dual-luciferase reporter assay, WNV NS1 significantly inhibited the activation of the IFN-ß promoter after Sendai virus infection or poly(I·C) treatment. NS1 also suppressed the activation of the IFN-ß promoter when it was stimulated by interferon regulatory factor 3 (IRF3)/5D or its upstream molecules in the RLR signaling pathway. Furthermore, NS1 blocked the phosphorylation and nuclear translocation of IRF3 upon stimulation by various inducers. Mechanistically, WNV NS1 targets RIG-I and melanoma differentiation-associated gene 5 (MDA5) by interacting with them and subsequently causing their degradation by the proteasome. Furthermore, WNV NS1 inhibits the K63-linked polyubiquitination of RIG-I, thereby inhibiting the activation of downstream sensors in the RLR signaling pathway. Taken together, our results reveal a novel mechanism by which WNV NS1 interferes with the host antiviral response.IMPORTANCE WNV Nile virus (WNV) has received increased attention since its introduction to the United States. However, the pathogenesis of this virus is poorly understood. This study demonstrated that the nonstructural protein 1 (NS1) of WNV antagonizes the induction of interferon beta (IFN-ß) by interacting with and degrading retinoic acid-inducible gene I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5), which are crucial viral sensors in the host innate immune system. Further experiments suggested that NS1-mediated inhibition of the RIG-I-like receptor (RLR) signaling pathway involves inhibition of RIG-I K63-linked polyubiquitination and that the proteasome plays a role in RIG-I degradation. This study provides new insights into the regulation of WNV NS1 in the RLR signaling pathway and reveals a novel mechanism by which WNV evades the host innate immune response. The novel findings may guide us to discover new therapeutic targets and develop effective vaccines for WNV infections.


Assuntos
Proteína DEAD-box 58/metabolismo , Interações Hospedeiro-Patógeno , Evasão da Resposta Imune , Helicase IFIH1 Induzida por Interferon/metabolismo , Interferon beta/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Vírus do Nilo Ocidental/patogenicidade , Animais , Linhagem Celular , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Receptores Imunológicos , Vírus do Nilo Ocidental/imunologia
6.
Neural Regen Res ; 10(1): 99-103, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25788928

RESUMO

Cutaneous nerve injury is the most common complication following foot and ankle surgery. However, clinical studies including long-term follow-up data after cutaneous nerve injury of the foot and ankle are lacking. In the current retrospective study, we analyzed the clinical data of 279 patients who underwent foot and ankle surgery. Subjects who suffered from apparent paresthesia in the cutaneous sensory nerve area after surgery were included in the study. Patients received oral vitamin B12 and methylcobalamin. We examined final follow-up data of 17 patients, including seven with sural nerve injury, five with superficial peroneal nerve injury, and five with plantar medial cutaneous nerve injury. We assessed nerve sensory function using the Medical Research Council Scale. Follow-up immediately, at 6 weeks, 3, 6 and 9 months, and 1 year after surgery demonstrated that sensory function was gradually restored in most patients within 6 months. However, recovery was slow at 9 months. There was no significant difference in sensory function between 9 months and 1 year after surgery. Painful neuromas occurred in four patients at 9 months to 1 year. The results demonstrated that the recovery of sensory function in patients with various cutaneous nerve injuries after foot and ankle surgery required at least 6 months.

7.
J Magn Reson Imaging ; 41(1): 142-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24470398

RESUMO

PURPOSE: After observing prominent cisterna chyli in several patients with autosomal dominant polycystic kidney disease (ADPKD), we investigated the potential association of cistern chyli enlargement with ADPKD. MATERIALS AND METHODS: Retrospective, cross-sectional analysis of abdominal and pelvic MRI at 1.5 Tesla (T) in 70 ADPKD patients (male 44.3%, 20-83 years, median = 53 years) were compared with 70 age and gender matched control subjects without ADPKD, cirrhosis, or cholestasis. Cisterna chyli diameter was measured on axial single shot fast spin echo (SSFSE) images at the level of T12-L2 and evaluated by multivariable regression models with covariates including estimated glomerular filtration rate (eGFR), total kidney volume (TKV), renal cyst fraction (cyst volume/kidney volume), and liver volume. RESULTS: Subjects with ADPKD had larger median cisterna chyli diameter compared with those without ADPKD (6.1 mm versus 3.4 mm, P < 0.0001). The prevalence of cisterna chyli enlargement more than the median (3.4 mm), was greater in ADPKD than in controls (99% versus 51%, P < 0.0001). On univariate analysis, cisterna chyli diameter was inversely correlated with eGFR (r = -0.41; P < 0.0001) and directly correlated with TKV (r = 0.57; P < 0.0001), total renal cyst fraction (r = 0.61; P < 0.001), and liver volume (r = 0.17; P = 0.040). Multivariable linear regression modeling found a significant association of cisterna chyli diameter with ADPKD diagnosis (B = 2.14; 95% confidence interval [CI]: 0.05-4.23; P = 0.04). Logistic regression analysis confirmed the association of ADPKD with an enlarged cisterna chyli diameter (odds ratio = 68.4; 95%CI: 8.9-524, P < 0.0001). CONCLUSION: Enlarged cisterna chyli is highly prevalent in ADPKD patients but not in age and gender-matched controls.


Assuntos
Imageamento por Ressonância Magnética/métodos , Rim Policístico Autossômico Dominante/patologia , Ducto Torácico/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Retrospectivos , Adulto Jovem
8.
Yao Xue Xue Bao ; 47(5): 664-9, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22812014

RESUMO

Aeroto-Niu-O16, an oxygen-tolerant bovine rumen bacterium, is capable of aerobically reducing isoflavones daidzein and genistein to dihydrodaidzein and dihydrogenistein through catalytic hydrogenation. In this study, it was found that bacterium strain Aeroto-Niu-O16 was able to cleavage the C-ring of liquiritigenin (LG), which is one of the main biologically active components of licorice roots, in the presence of atmospheric oxygen. LG was prepared by acid hydrolysis of the crude extract of licorice roots. The metabolite of LG obtained in strain Aeroto-Niu-O16 was identified as davidigenin (DG) based on the data of UV, MS, 1H and 13C NMR. The maximal concentration of LG that the strain Aeroto-Niu-O16 was able to transform effectively was 0.8 mmol x L(-1) and the average productivity of the metabolite DG was 71.7%. Furthermore, when 0.1% (m/v) of L-cysteine or sodium thiosulfate was added in the cultural medium, the average bioconversion rate of LG was increased from 71.7% to 78.3% and 77.2%, respectively. The in vitro antioxidant investigation showed that 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity of DG was significantly or extremely significantly higher than that of LG at the concentrations from 0.2 mmol x L(-1) to 1.6 mmol x L(-1). We discoverd for the first time that LG can be converted to DG, which has stronger and wider biological activities, through microbial biotransformation method.


Assuntos
Antioxidantes/metabolismo , Bactérias Anaeróbias/metabolismo , Chalcona/análogos & derivados , Flavanonas/metabolismo , Glycyrrhiza/química , Animais , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Bactérias Anaeróbias/isolamento & purificação , Biotransformação , Compostos de Bifenilo/metabolismo , Bovinos , Chalcona/metabolismo , Chalcona/farmacologia , Cisteína/farmacologia , Flavanonas/isolamento & purificação , Flavanonas/farmacologia , Picratos/metabolismo , Raízes de Plantas/química , Plantas Medicinais/química , Rúmen/microbiologia , Tiossulfatos/farmacologia
9.
JACC Cardiovasc Imaging ; 4(11): 1206-16, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22093272

RESUMO

Discovery of an association between gadolinium-based contrast agents (GBCAs) and nephrogenic systemic fibrosis (NSF) has led to less use of GBCA-enhanced magnetic resonance imaging in dialysis patients and patients with severe renal failure at risk of NSF, and the virtual elimination of new cases of NSF. But shifting patients with renal failure to alternative imaging methods may subject patients to other risks (e.g., ionizing radiation or iodinated contrast). This review paper examines 370 NSF cases reported in 98 articles to analyze NSF risk factors. Eliminating multiple risk factors by limiting GBCA dose to a maximum of 0.1 mmol/kg, dialyzing patients undergoing dialysis quickly following GBCA administration, delaying GBCA in acute renal failure until after renal function returns or dialysis is initiated, and avoiding nonionic linear GBCA in patients with renal failure especially when there are proinflammatory conditions may substantially reduce the risk of NSF.


Assuntos
Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Dermopatia Fibrosante Nefrogênica/patologia , Insuficiência Renal/complicações , Pele/patologia , Biópsia , Relação Dose-Resposta a Droga , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Imageamento por Ressonância Magnética , Dermopatia Fibrosante Nefrogênica/etiologia , Dermopatia Fibrosante Nefrogênica/fisiopatologia , Dermopatia Fibrosante Nefrogênica/prevenção & controle , Seleção de Pacientes , Diálise Renal , Insuficiência Renal/fisiopatologia , Insuficiência Renal/terapia , Medição de Risco , Fatores de Risco
10.
Orthop Surg ; 3(1): 52-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22009981

RESUMO

OBJECTIVE: To observe the accuracy of computer-assisted navigation (CAN) in cervical pedicle screw installation and to analyze the reasons for screw malposition. METHODS: From October 2004 to December 2009, 144 cervical pedicle screws were installed in 25 patients with cervical spinal diseases using CAN. Screw position and direction were measured on sagittal and transection images from intraoperative navigation and postoperative CTs. RESULTS: Among 144 screws inserted from C3 to C7, two perforated the upper pedicle wall and three deviated from the lateral pedicle wall. The rate of accurate cervical pedicle screw placement with CAN was 96.5% (139/144) in our group. There was no statistical difference in the position and direction of the pedicle screws according to navigation images and CT scans. CONCLUSION: CAN can result in high accuracy of cervical pedicle installation. The excursion phenomenon is responsible for malposition of pedicle screws. Only by understanding the navigational principles of CAN and the characteristics of cervical spinal surgery, together with personal experience, can good use be made of CAN.


Assuntos
Parafusos Ósseos , Vértebras Cervicais/cirurgia , Doenças da Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodos , Adulto , Idoso , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/lesões , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos , Doenças da Coluna Vertebral/diagnóstico por imagem , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/normas , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto Jovem
11.
J Magn Reson Imaging ; 30(6): 1298-308, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19937930

RESUMO

Emerging evidence linking gadolinium-based contrast agents (GBCAs) to nephrogenic systemic fibrosis (NSF) has changed medical practice patterns toward forgoing GBCA-enhanced magnetic resonance imaging (MRI) or substituting other imaging methods, which are potentially less accurate and often radiation-based. This shift has been based on reports of high NSF incidence at sites where a confluence of risk factors occurred in patients with severe renal dysfunction. This review article explores the factors that affect NSF risk, compares risks of alternative imaging procedures, and demonstrates how risk can be managed by careful selection of GBCA dose, timing of injection with respect to dialysis, and other factors. Nearly half of NSF cases are a milder form that does not cause contractures or reduce mobility. It appears that eliminating even a single risk factor can reduce NSF incidence/risk at least 10-fold. Elimination of multiple risk factors by using single-dose GBCA, dialyzing dialysis patients quickly following GBCA administration, avoiding GBCA in acute renal failure while serum creatinine is rising, and avoiding nonionic linear GBCA in renal failure patients may reduce NSF risk more than a thousand-fold, thereby allowing safe GBCA-enhanced MRI in virtually all patients. J. Magn. Reson. Imaging 2009;30:1298-1308. (c) 2009 Wiley-Liss, Inc.


Assuntos
Gadolínio , Imageamento por Ressonância Magnética/estatística & dados numéricos , Dermopatia Fibrosante Nefrogênica/epidemiologia , Dermopatia Fibrosante Nefrogênica/prevenção & controle , Meios de Contraste , Humanos , Incidência , Medição de Risco , Fatores de Risco
12.
J Magn Reson Imaging ; 29(5): 1085-92, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19388123

RESUMO

PURPOSE: To identify changes in vascular morphology on magnetic resonance imaging (MRI) in patients with cirrhosis and to compare these findings to liver donors. MATERIALS AND METHODS: Patients undergoing liver transplantation with biopsy-proven cirrhosis (n = 74) and liver donor candidates (n = 85) underwent dynamic gadolinium-enhanced 3D MR at 1.5T. Vessel diameters were measured independently by three radiologists and features of cirrhosis were identified and correlated with cirrhosis. RESULTS: Hepatic veins were smaller in patients with cirrhosis (4.9, 4.5, and 5.0 mm for right, middle, and left vs. 9.9, 7.6, and 8.9 mm in donors, P << 0.001) and were negatively correlated with cirrhosis (P < 0.001). Right hepatic vein (RHV) <5 mm diagnosed cirrhosis with 59% sensitivity and 99% specificity; the sensitivity and specificity were 88% and 85% for RHV <7 mm. Main portal vein was minimally larger in cirrhosis, 14 versus 12 mm (P < 0.001) in donors. Right portal veins were smaller in cirrhotic patients, 6.5 and 6.2 mm compared to 8.4 and 7.6 mm (P << 0.001), respectively, in donors. CONCLUSION: Vascular features of cirrhosis include small hepatic veins, minimally enlarged main portal vein, and small intrahepatic portal veins; these features may facilitate identification of cirrhosis.


Assuntos
Veias Hepáticas/patologia , Cirrose Hepática/patologia , Transplante de Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Doadores de Tecidos
13.
J Magn Reson Imaging ; 27(6): 1309-16, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18504761

RESUMO

PURPOSE: To determine how dynamic contrast-enhanced (DCE) MRI at 3T correlates with rectal carcinoma angiogenesis. MATERIALS AND METHODS: Three-dimensional (3D) DCE MRI was performed in 38 patients (23 males, 15 females, mean age 60 years) with histologically-confirmed rectal carcinoma at 3T. Time-intensity curves (TICs) were used to measure peak enhancement ratio (ER(peak)), time to peak enhancement (T(peak)), first enhancement time (T(first-enhance)), and uptake rate for rectal tumor, normal rectal wall, and gluteal muscle. After tumor resection, microvascular density (MVD) and vascular endothelial growth factor (VEGF) expression were determined using immunohistochemistry (IHC) stains on available specimens (N = 24) to correlate with DCE MRI. RESULTS: Rectal carcinoma showed higher ER(peak) (3.0 +/- 0.9 vs. 1.9 +/- 0.9, P < 0.001), higher uptake rate (2.8 +/- 1.5/minute vs. 1.2 +/- 0.9/minute, P < 0.001), earlier T(peak) (88 +/- 56 seconds vs. 124 +/- 72 seconds, P = 0.027), and earlier T(first-enhance) (34 +/- 6 seconds vs. 40 +/- 7 seconds, P = 0.008) than normal rectal wall. Adenocarcinoma had shorter T(peak) compared to signet cell carcinoma (77 +/- 48 seconds vs. 160 +/- 62 seconds, P = 0.004). T(peak) was negatively correlated with MVD (r = -0.516, P = 0.01) and the mean T(peak) was significantly earlier for the VEGF-positive group compared to the VEGF-negative group (57 +/- 17 seconds vs. 107 +/- 64 seconds, P = 0.021). CONCLUSION: DCE MRI parameters help predict rectal tumor angiogenesis measured by MVD and VEGF expression and discriminate malignant from normal tissue.


Assuntos
Adenocarcinoma/irrigação sanguínea , Carcinoma de Células em Anel de Sinete/irrigação sanguínea , Meios de Contraste/administração & dosagem , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Neovascularização Patológica/diagnóstico , Neoplasias Retais/irrigação sanguínea , Adenocarcinoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Carcinoma de Células em Anel de Sinete/diagnóstico , Feminino , Gadolínio DTPA , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/instrumentação , Magnetismo , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/diagnóstico , Reto/irrigação sanguínea , Reto/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
AJR Am J Roentgenol ; 190(5): 1271-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18430843

RESUMO

OBJECTIVE: The purpose of this study was to assess the accuracy of 3-T MRI in the preoperative diagnosis, staging, and planning of surgical management of rectal carcinoma. SUBJECTS AND METHODS: Thirty-eight patients (23 men, 15 women) with clinically suspected rectal carcinoma underwent 3-T MRI. Coronal, axial, and sagittal T2-weighted sequences with and without fat suppression; axial T1-weighted spin-echo sequences; axial T1-weighted gradient-echo sequences with and without fat suppression; oblique 2D MR hydrography; and 3D fat-suppressed dynamic contrast-enhanced MRI were performed. Image quality with these sequences was evaluated by three radiologists experienced in body MRI. The significance of difference in results with the sequences was tested. The manner in which MRI staging and feasibility of sphincter-sparing surgery agreed with operative and pathologic findings was evaluated with kappa statistics. RESULTS: Rectal carcinoma was identified on MRI and confirmed histologically in all 38 patients. MRI findings were correctly predictive of T category in 35 cases (accuracy, 92.1%). In 31 (96.9%) of 32 resectable cases,sphincter-sparing surgical approaches were accurately chosen on the basis of MRI findings. Among the 11 sequences, 3D fat-suppressed dynamic contrast-enhanced MRI best delineated tumor margins. Coronal and axial T2-weighted images also well depicted tumor margins with minimal artifact. T2-weighted images were superior to unenhanced T1-weighted images. CONCLUSION: MRI of rectal cancer at 3 T is accurate for prediction of T category and the feasibility of sphincter-sparing surgery. The best images were obtained with coronal, sagittal, and axial T2-weighted sequences and 3D fat-suppressed dynamic contrast-enhanced MRI.


Assuntos
Carcinoma/patologia , Carcinoma/cirurgia , Imageamento por Ressonância Magnética , Neoplasias Retais/patologia , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
15.
J Xray Sci Technol ; 11(4): 231-40, 2003 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22388293

RESUMO

PURPOSE: To evaluate the imaging potential of ferumoxytol, a new superparamagnetic iron oxide colloidal blood pool contrast agent. MATERIALS AND METHODS: Magnetic resonance (MR) imaging at 1.5 Tesla was performed before and after intravenous injection of ferumoxytol using escalating doses of 0.4, 0.8, 1.2 and 1.6 mg Fe/kg for a total of 4 mg Fe/kg in five subjects imaged with 3D MR Angiography (MRA) of the trifurcation after each dose. In five subjects cardiac cine MRI was performed pre and post 4.0 mg Fe/kg. Image quality was assessed by measuring signal to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in the vascular structures. Pre- and post-dose urine and blood tests as well as EKG/vital sign monitoring were performed to evaluate safety and blood samples were collected for T1 relaxivity measurements. RESULTS: Cumulative doses of 0, 0.4, 1.2, 2.4 and 4 mg Fe/kg yielded mean SNR in the arteries of 10, 16, 39, 57 and 69 respectively indicating that the higher doses produced higher SNR on 3D vascular images. Similarly aorta SNR on 2D time-of-flight increased from 11.8 without Fe to 15.4 post Fe (p = 0.004) indicating improved image quality on MRA sequences optimized for use without contrast. At 4 mg Fe/kg there was a substantial T1 shortening measured in the blood from 1990 ± 573 ms to 80 ± 42 ms (p < 0.0001), corresponding to the increased SNR. Images of large vascular structures including cardiac chambers, aorta, and pulmonary arteries were excellent post ferumoxytol but images of smaller arteries of the trifurcation were difficult to evaluate due to enhancement of the overlapping veins. No serious adverse events occurred. CONCLUSION: The new superparamagnetic iron oxide colloid ferumoxytol is a promising blood pool agent especially for cardiac, aorta and pulmonary imaging.

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