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41.
Oka K Yakushiji T Sato H Yorimitsu S Hayashida Y Yamashita Y Mizuta H 《Journal of magnetic resonance imaging : JMRI》2008,28(5):1195-1200
Purpose
To evaluate the potential of diffusion‐weighted imaging (DWI) in distinguishing chronic expanding hematomas (CEHs) from malignant soft tissue tumors.Materials and Methods
We performed conventional MRI and DWI of six CEHs and 31 malignant soft tissue tumors from 37 patients seen between May 2000 and November 2006. DWI was obtained with a single‐shot echo‐planar imaging (EPI) sequence using a 1.5T MR imager. The mean apparent diffusion coefficient (ADC) value was also calculated. We evaluated MRI findings of CEHs and compared ADC value of CEHs with malignant soft tissue tumors.Results
On conventional MRI, two of six CEHs were difficult to differentiate from malignant soft tissue tumors based on imaging findings. The mean ADC value of CEHs and malignant soft tissue tumors was 1.55 ± 0.121 × 10?3 mm2/sec and 0.92 ± 0.139 × 10?3 mm2/sec (mean ± SD), respectively. The mean ADC value of CEHs was significantly higher than that of malignant soft tissue tumors (P < 0.01). There was no overlap in the minimum ADC values among CEHs and malignant soft tissue tumors.Conclusion
DWI is useful for differentiating between CEHs and malignant soft tissue tumors. J. Magn. Reson. Imaging 2008;28:1195–1200. © 2008 Wiley‐Liss, Inc.42.
Comparison of grey matter and metabolic reductions in frontotemporal dementia using FDG-PET and voxel-based morphometric MR studies 总被引:1,自引:0,他引:1
Kanda T Ishii K Uemura T Miyamoto N Yoshikawa T Kono AK Mori E 《European journal of nuclear medicine and molecular imaging》2008,35(12):2227-2234
Purpose The aim of this study was to investigate the regional differences between the morphologic and functional changes in the same
patients with frontotemporal dementia (FTD) using statistical parametric mapping and voxel-based morphometry (VBM).
Methods Thirteen FTD patients (mean age, 64.9 years old; mean MMSE score, 17.7), 20 sex-matched Alzheimer’s disease (AD) patients
(mean age, 65.0 years old; mean MMSE score, 17.5), and 20 normal volunteers (mean age, 65.2 years old; mean MMSE score, 29.0)
underwent both [18F]FDG positron emission tomography and three-dimensional spoiled gradient echo MRI. Statistical parametric mapping was used
to conduct a VBM analysis of the morphologic data, which were compared voxel by voxel with the results of a similar analysis
of glucose metabolic data.
Results FTD patients showed decreased grey matter volume and decreased glucose metabolism in the frontal lobe and anterior temporal
lobe. In addition, there was a clear asymmetry in grey matter volume in FTD patients by the VBM analysis while the glucose
metabolic data showed little asymmetry. In AD patients, glucose metabolic reduction occurred in the bilateral posterior cingulate
gyri and parietal lobules while grey matter density decreased the least in the same patients.
Conclusion In FTD, metabolic and morphologic changes occur in the bilateral frontal lobe and temporal lobe with a limited asymmetry whereas
there was considerable discordance in the AD group. 相似文献
43.
Ishii K Kanda T Harada A Miyamoto N Kawaguchi T Shimada K Ohkawa S Uemura T Yoshikawa T Mori E 《European radiology》2008,18(11):2678-2683
The utility of measuring the corpus callosal angle (CA) for the diagnosis of idiopathic normal pressure hydrocephalus (INPH)
was investigated. Three-dimensional magnetic resonance imaging (MRI) was performed in 34 INPH patients, 34 Alzheimer’s disease
(AD) patients, and 34 normal control (NC) subjects. Measurement of the CA on the coronal MR images of the posterior commissure
perpendicular to the anteroposterior commissure plane was performed for all subjects. The CA of the INPH group (mean ± SD,
66 ± 14°) was significantly smaller than those of the AD (104 ± 15°) and NC (112 ± 11°) groups. When using the threshold of
the mean − 2SD value of the NC group (= 90°), an accuracy of 93%, sensitivity of 97%, and specificity of 88% were observed
for discrimination of INPH from AD patients. Measuring the CA helps in differentiating INPH patients from AD and normally
aged subjects. 相似文献
44.
45.
Nakada I Tabuchi T Nakachi T Shimazaki J Konishi S Katano M Ubukata H Goto Y Watanabe Y Tabuchi T 《Surgery today》2008,38(8):675-678
We analyzed the histological high-risk factors for recurrence of submucosal invasive carcinomas (pT1) of the colon and rectum after endoscopic therapy, examining pT1 cancers treated primarily by endoscopic resection within a 23-year period. We compared recurrent and nonrecurrent cancers, evaluating the following "highrisk factors" of the primary lesion: massive invasion, a surgical margin <2 mm but negativity for cancer in the cut end, poorly differentiated adenocarcinoma (PD) (G3), undifferentiated carcinoma (G4), and/or positive angiolymphatic invasion. The following histological factors were defined as predictive of a low risk: minimum invasion, a surgical margin >2 mm, well or moderately differentiated adenocarcinoma (G1, G2), and no evidence of angiolymphatic invasion. We analyzed the records of 37 patients with pT1 cancers, including 15 with high-risk factors who underwent subsequent resection. Local recurrence with or without liver metastases developed in 4 of these 15 patients. The histological type was PD in three (75%) of the four recurrent lesions. All four (100%) lesions showed a desmoplastic response (DR). Only 1 (9%) of the 11 patients without recurrence after subsequent surgery had a lesion with a small component of PD, and only three (27%) lesions showed a mild DR. We concluded that endoscopic therapy is inadequate for pT1 cancers with a histological PD component, and/or a DR in the cancer stroma. 相似文献
46.
Improvement of the survival rate by fetal liver cell transplantation in a mice lethal liver failure model 总被引:1,自引:0,他引:1
Machimoto T Yasuchika K Komori J Ishii T Kamo N Shimoda M Konishi S Saito M Kohno K Uemoto S Ikai I 《Transplantation》2007,84(10):1233-1239
BACKGROUND: The use of cell transplantation as an alternative therapy for orthotopic liver transplantation has been widely anticipated due to a chronic donor shortage. We previously reported the method used to enrich hepatic progenitor cells (HPCs) forming cell aggregations. In this study, we transplanted HPCs into the liver injury model mice to determine whether HPC transplantation may improve the liver dysfunction. METHODS: We obtained donor cells from E13.5 fetal livers of green fluorescent protein (GFP) transgenic mice. We transplanted GFP-positive fetal liver cells into the transgenic mice which express diphtheria toxin (DT) receptors under the control of an albumin enhancer/promoter. Subsequently, we induced selective liver injury to recipient mice by DT administration. We then evaluated the engraftment of the transplanted cells and their effect on survivorship. RESULTS: The low dose of DT induced sublethal liver injury and the high dose of DT was lethal to the liver injury model mice. The transplanted GFP-positive cells were engrafted into the recipient livers and expressed albumin, resembling mature hepatocytes. They continued to proliferate, forming clusters. The survival rate at 25 days after transplantation of the cell-transplanted group (8 of 20; 40.0%) was improved significantly (P=0.0047) in comparison to that of the sham-operated group (0 of 20; 0%). CONCLUSIONS: The transplanted cells were engrafted and repopulated the liver of recipient mice, resulting in the improvement of the survival rate of the liver injury model mice. We therefore propose that HPCs are a desirable cell source for cell transplantation. 相似文献
47.
Prognostic Significance of Immunohistochemically Detected Blood and Lymphatic Vessel Invasion in Colorectal Carcinoma: Its Impact on Prognosis 总被引:6,自引:0,他引:6
Liang P Nakada I Hong JW Tabuchi T Motohashi G Takemura A Nakachi T Kasuga T Tabuchi T 《Annals of surgical oncology》2007,14(2):470-477
Background The prognostic significance of blood vessel invasion (BVI) and lymphatic vessel invasion (LVI) is unclear. Because of the
absence of specific markers for venous and lymphatic vessels, earlier studies could not reliably distinguish between BVI and
LVI.
Methods By immunostaining for podoplanin and CD34 antigen, we retrospectively investigated LVI and BVI in 419 tissue specimens of
colorectal carcinoma. We performed univariate and multivariate analysis of the clinicopathologic features, frequency of recurrence,
and outcome of patients with or without LVI and BVI.
Results The use of hematoxylin and eosin (H&E) staining to identify BVI and LVI yielded a false positive rate of 9.1% and false negative
rate of 12.6%. The incidence of BVI was significantly higher among tumors with LVI than tumors without LVI (P <.001). In logistic multivariate analysis, only LVI (P < .001) was associated with lymph node metastasis and BVI (P = .015) was associated with distant recurrence. Calculating the prognostic relevance, both two invasion types correlated
with decreased survival in univariate analysis (both P <.001). In multivariate analysis, BVI (P =.024), lymph node status (P =.003) and tumor stage (P <.001) remained statistically significant factors for survival.
Conclusions Our results suggest that immunohistologic evaluation of BVI and LVI could be useful in colorectal carcinoma indicating the
risk of lymph node metastasis and recurrence, thereby contributing to prognostic evaluation. 相似文献
48.
Background Interleukin (IL)-6, cyclooxygenase (COX)-2, and monocyte chemoattractant protein (MCP)-1 contribute to renal injury. The promoter
regions of these genes contain CCAAT/enhancer-binding protein (C/EBP)-binding sites. In this study, we investigated the role
of C/EBP-δ in mesangial cells (MCs).
Methods In an in vivo study, anti-Thy 1.1 glomerulonephritis rats were generated and C/EBP-δ, IL-6, COX-2, and MCP-1 expressions were
assessed by immunohistochemistry. In an in vitro study, cultured MCs were transfected with non-silencing (NS) short interfering
RNA (siRNA) or C/EBP-δ siRNA. Subsequently, after stimulation with IL-1β, C/EBP-δ, IL-6, COX-2, and MCP-1 mRNA expression levels were evaluated using real-time polymerase chain reaction (PCR). IL-6 concentration in the culture
medium was determined by enzyme-linked immunosorbent assay. In addition, cell proliferative activity against IL-1β or platelet-derived
growth factor-BB was assessed by bromodeoxyuridine incorporation.
Results In the in vivo study, C/EBP-δ, IL-6, COX-2, and MCP-1 were expressed in the mesangial region of anti-Thy 1.1 glomerulonephritis
rats on day 1. In the in vitro study, IL-1β increased C/EBP-δ mRNA levels in NS siRNA-transfected MCs (7.3-fold), but no increase was evident in C/EBP-δ siRNA-transfected MCs. IL-6, COX-2, and MCP-1 mRNA levels in C/EBP-δ siRNA-transfected MCs were all lower than those in NS siRNA-transfected MCs (decreases of 57.7%, 85.7%,
and 69.3%, respectively). The IL-6 concentration in the culture medium from C/EBP-δ siRNA transfected MCs (7.37 ± 4.3 pg/ml)
was also lower than that in the culture medium from NS siRNA-transfected MCs (25.2 ± 3.4 pg/ml). Cell proliferative activity
in C/EBP-δ siRNA-transfected MCs was lower than that in NS siRNA transfected MCs.
Conclusions C/EBP-δ was induced in the mesangial region during the early stages of anti-Thy1.1 glomerulonephritis. C/EBP-δ contributes
to inflammatory gene expression and MC proliferation. 相似文献
49.
A 32-year-old man presented with an arachnoid cyst of the posterior fossa manifesting as cervical syringomyelic myelopathy. Magnetic resonance (MR) imaging demonstrated edematous enlargement and T2 prolongation of the cervical spinal cord, indicating a "presyrinx" state. MR imaging showed the inferior wall of the cyst, which disturbed cerebrospinal fluid (CSF) pulsatile movement between the intraspinal and intracranial subarachnoid spaces. The cyst wall was fenestrated with a neuroendoscope. The presyrinx state and the CSF movement improved. Posterior fossa arachnoid cyst, as well as Chiari malformation, can cause CSF flow disturbance at the craniocervical junction and syringomyelia. Endoscopic fenestration is less invasive than foramen magnum decompression and should be the procedure of choice. 相似文献
50.
Nobuaki Chinzei Takafumi Hiranaka Takahiro Niikura Mitsuo Tsuji Ryosuke Kuroda Minoru Doita Masahiro Kurosaka 《Clinics in Orthopedic Surgery》2015,7(3):291-297