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11.
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease.  相似文献   
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Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.

Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.

Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.

Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2.  相似文献   
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The development of new treatments for metabolic syndrome is urgent project for decreasing the prevalence of coronary heart disease and diabetes mellitus in the advanced countries. Peroxisome proliferator-activated receptor (PPAR)alpha and gamma agonists have shed light on the treatment of hypertriglyceridemia and type 2 diabetes mellitus, respectively. Among PPARs, analysis of the PPARdelta functions is lagging behind because specific PPARdelta agonists have not been developed. The appearance of new PPARdelta agonists is brightening the prospects for elucidating the physiological role of PPARdelta. PPARdelta is a new target for the treatment of metabolic syndrome. In particular, the fact that fatty acid oxidation and energy dissipation in skeletal muscle and adipose tissue by PPARdelta agonists lead to improved lipid profile, reduced adiposity and insulin sensitivity is a breakthrough. It seems that treatment of PPARdelta agonists operate similarly to the caloric restriction and prolonged exercise. We suggest that the physiological role of PPARdelta may be an indicator for switching from glucose metabolism to fatty acid metabolism. To receive new benefits of PPARdelta agonists against metabolic syndrome by increasing fatty acid consumption in skeletal muscle and adipose tissue, we need to unveil more details on the functions of PPARdelta itself and its agonists in the future.  相似文献   
16.
Background and Aims: Video capsule endoscopy (VCE) has become increasingly important as a simple method for observing the entire small intestine. The indications for VCE are obscure gastrointestinal bleeding and investigation of Crohn’s disease (CD). However, the correlation between endoscopic findings obtained by VCE and clinical findings in known cases of CD is not clear, and we therefore investigated this in the present study. Patients and methods: In 30 patients with known CD (Crohn’s disease activity index [CDAI] 0–420; median = 158.3), double contrast enteroclysis (ENT) was performed 1–3 weeks prior to VCE. The relationship between the VCE findings and hematological analysis/CDAI was examined. Results: In 17 of 30 patients, the entire small intestine could be investigated by VCE, whereas in the remaining 13 patients the terminal ileum could not be investigated. The following exhibited positive correlations: total lesions and CDAI (correlation coefficient values: rs = 0.661, adjusted P < 0.0061), ulcers and C‐reactive protein (CRP) (rs = 0.607, adjusted P < 0.0061), total lesions and CRP (rs = 0.604, adjusted P < 0.0061). Conclusions: Analysis with VCE suggests that CDAI and CRP indicate the activity of intestinal lesions in patients with known CD, and that CRP, in particular, is associated with the activity of ulcerative lesions of the intestine. This may contribute to revised guidelines for VCE in the future.  相似文献   
17.
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese.  相似文献   
18.
We describe a case of aldosterone-producing adrenocortical adenoma (APA) associated with a probable post-operative adrenal crisis possibly due to subtle autonomous cortisol secretion. The patient was a 46-year-old female who suffered from severe hypertension and hypokalemia. CT and MRI scans revealed a 2-cm diameter adrenal mass. The patient's plasma aldosterone level was increased, and her plasma renin activity was suppressed, both of which findings were consistent with APA. Cushingoid appearance was not observed. Morning and midnight serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels were all within the normal range. Her serum cortisol level was suppressed to 1.9 microg/dl as measured by an overnight 1-mg dexamethasone suppression test, but was incompletely suppressed (2.7 microg/dl) by an overnight 8-mg dexamethasone suppression test. In addition, adrenocortical scintigraphy showed a strong uptake at the tumor region and a complete suppression of the contra-lateral adrenal uptake. After unilateral adrenalectomy, she had an episode of adrenal crisis, and a transient glucocorticoid replacement improved the symptoms. Histopathological studies demonstrated that the tumor was basically compatible with APA. The clear cells in the tumor were admixed with small numbers of compact cells that expressed 17alpha-hydroxylase, suggesting that the tumor was able to produce and secrete cortisol. In addition, the adjacent non-neoplastic adrenal cortex showed cortical atrophy, and dehydroepiandrosterone sulfotransferase immunoreactivity in the zonae fasciculata and reticularis was markedly diminished, suggesting that the hypothalamo-pituitary-adrenal (HPA) axis of the patient was suppressed due to neoplastic production and secretion of cortisol. Together, these findings suggested that autonomous secretion of cortisol from the tumor suppressed the HPA axis of the patient, thereby triggering the probable post-operative adrenal crisis. Post-operative adrenocortical insufficiency should be considered in clinical management of patients with relatively large APA, even when physical signs of autonomous cortisol overproduction are not apparent.  相似文献   
19.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
20.
From April 1989 to December 2004, we performed liver biopsy on 475 patients and obtained biopsy proven 35 cases of non-alcoholic fatty liver. Among them, 18 cases were diagnosed as non-alcoholic steatohepatitis (NASH). During the last three years, we have tried to detect NASH using ultrasonography and elevated value of serum ferritin (> 300 ng/ml). All of the eligible 7 cases biopsied during the course were diagnosed as NASH. In these 7 cases, ALT levels improved after the body weight loss accompanied by the parallel decrease of serum ferritin levels. Measurement of serum ferritin is useful in the detection of NASH but the normal value of ferritin cannot rule out the possibility of NASH.  相似文献   
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