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Full length cDNA and gene encoding ghrelin precursor and mature ghrelin peptide were identified from the stomach of Pacific bluefin tuna, Thunnus orientalis, which has unique metabolic physiology and high commercial value at fishery markets. Quantitative expression analysis was conducted for the gastric ghrelin and pepsinogen 2 genes during the early stage of somatic growth from the underyearling to yearling fish. The full length cDNA of bluefin tuna ghrelin precursor has a length of 470bp and the deduced precursor is composed of 107 amino acids. The ghrelin gene is 1.9kbp in length and has a 4 exon-3 intron structure. The major form of mature ghrelin in the stomach was an octanoylated 20-amino acid peptide with C-terminal amidation, while overall 12 different forms of ghrelin peptides, including short form of 18-amino acid peptide and seven kinds of acyl modifications were identified. The expression profiles of the gastric ghrelin and pepsinogen 2 genes showed no significant changes related to the early growth stages. The present results suggest that digestive physiology has already been functional in this growth stage of the juvenile bluefin tuna and ghrelin may have a role in the sustained digestive and metabolic activities.  相似文献   
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The aim of this study was to prospectively measure liver stiffness with real-time tissue elastography in patients with nonalcoholic fatty liver diseases (NAFLD) and to compare the result with the clinical assessment of fibrosis using histological stage. One hundred and eighty-one prospectively enrolled patients underwent real-time tissue elastography, with the first 106 being analyzed as the training set and the remaining 75 being evaluated as the validation set. Hepatic and splenic elastic ratios were calculated and compared with stage of histological fibrosis. Portal hypertension (PH) was assessed. Real-time tissue elastography cut-off values by stage in the training set were 2.47 for F1, 2.67 for F2, 3.02 for F3, and 3.36 for F4. Using these cut-off values, the diagnostic accuracy of hepatic fibrosis in the validation set was 82.6%-96.0% in all stages. Only portal fibrosis correlated with the hepatic elastic ratio by multivariate analysis. The area under the receiver operating characteristic curve of elastic ratio better correlated than serum fibrosis markers in both early and advanced fibrosis stages. Patients with PH, defined by splenic elasticity, had early fibrosis. Patients with severe PH were found only in the group with cirrhosis. Conclusion: Real-time tissue elastography is useful in evaluating hepatic fibrosis and PH in patients with NAFLD. (HEPATOLOGY 2012).  相似文献   
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Objectives

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is becoming common in Japan. Oral and maxillofacial radiologists must diagnose BRONJ in general practice. However, little information on how to recognise BRONJ is available. The purpose of this study, therefore, was to confirm the recognition of BRONJ among Japanese oral and maxillofacial radiologists.

Methods

A questionnaire including 14 main queries and relevant branch queries was created and sent to 29 Japanese institutions employing oral and maxillofacial radiologists.

Results

A large number of patients (705) with BRONJ during the last 3 years were reported by 23 institutions (25 responders) that participated in our survey. The rate of osteonecrosis of the jaw associated with intravenous bisphosphonates was almost identical to that associated with oral bisphosphonates. This finding was inconsistent with worldwide data. About half of the responders felt that the diagnosis of BRONJ based on imaging was difficult. No specific modality was selected for identifying the early signs of BRONJ, although 19 responders selected multi-detector computed tomography followed by magnetic resonance imaging as the best modality for determining the extent of BRONJ. Almost all responders felt that the detection of early signs and determination of lesion extent on imaging were important roles of oral and maxillofacial radiologists.

Conclusions

Oral and maxillofacial radiologists recognised their roles in BRONJ diagnosis; however, insufficient evidence regarding the accomplishment of these roles is available. Japanese oral and maxillofacial radiologists must accumulate a large number of BRONJ images, analyse them in cooperation with one another and share the information obtained from their analysis.  相似文献   
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