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71.
72.
Serum uric acid (UA) levels reflect circulating xanthine oxidase activity and oxidative stress production. Hyperuricemia has been identified in patients who have congestive heart failure and is a marker of poor prognosis in such patients. We investigated the relation between serum UA levels and Killip's classification suggestive of the severity of heart failure and whether hyperuricemia influences mortality of patients who have acute myocardial infarction (AMI). Using the Japanese Acute Coronary Syndrome Study database, we evaluated 1,124 consecutive patients who were hospitalized within 48 hours of onset of symptoms of AMI from January to December 2002. There was a close relation between serum UA concentration and Killip's classification. Patients who developed short-term adverse events had high UA concentrations. Serum UA levels, Killip's class, age, and peak creatine phosphokinase level were significant predictors of long-term mortality. The hazard ratio for patients in the highest quartile of UA was 3.7 compared with those in the lowest quartile for death after AMI after adjustment for independent factors that were related to mortality. The combination of the best UA cutoff (447 micromol/L) for predicting survival based on receiver-operating characteristics analysis and Killip's class significantly predicted the prognosis of acute and long-term AMI-related complications. In conclusion, our results suggest that hyperuricemia after AMI is associated with the development of heart failure. Serum UA level is a suitable marker for predicting AMI-related future adverse events, and the combination of Killip's class and serum UA level after AMI is a good predictor of mortality in patients who have AMI.  相似文献   
73.
A 78-year-old man with hepatocellular carcinoma treated by chemoembolization and percutaneous ethanol injection was admitted to our hospital because of acute abdomen. The CT scan showed biliary fistula caused by hepatocellular carcinoma protruding from S3. Endoscopic retrograde cholangiopancreatography showed disruption of an intrahepatic duct and the main pancreatic duct, and contrast agent leaked into the peritoneal cavity from each duct. Omental panniculitis with biliary fistula and pancreatic fistula was diagnosed. The symptoms improved by endoscopic nasobiliary drainage and endoscopic pancreatic stenting. On the 13th day after admission, we added endoscopic nasopancreatic drainage because his abdominal pain had been exacerbated by pancreatic juice leakage. Omental panniculitis by hepatocellular carcinoma complicated by biliary fistula and pancreatic fistula is extremely rare. Endoscopic transpapillary pancreaticobiliary drainage was effective for omental panniculitis in this case.  相似文献   
74.
To date five mutations in two major constituents of neuronal nicotinic acetylcholine receptor (nAChR) in the brain, i.e. alpha4 and beta2 subunits, have been identified to be associated with autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE). Among them, only Ser284Leu, a point mutation in alpha4 subunit identified in ADNFLE as well as in a sporadic case with nocturnal frontal lobe epilepsy, remains to be characterized electrophysiologically. We examined the properties of rat nAChR harboring Ser284Leu reconstituted on Xenopus oocytes. Currents elicited in response to application of acetylcholine to oocytes expressing wild type or mutant nAChR were measured by a standard two-microelectrode voltage clamp method. Compared with wild-type nAChR, the mutant nAChR had a comparable EC(50) value for acetylcholine whereas it showed faster desensitization and lower Cs(+)/Na(+) permeability ratio. Ser284Phe, a putative mutation constructed for comparison, exhibited similar properties. These findings indicate that Ser(284) plays an important role in gating of nAChR along with Thr(276) and Ser(280), and suggest that mutation at Ser(284) could reduce nAChR activity similar to other mutations of alpha4 subunit found in ADNFLE.  相似文献   
75.

Objectives

To investigate whether amide proton transfer (APT) MR imaging can differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) among gliomas without intense contrast enhancement (CE).

Methods

This retrospective study evaluated 34 patients (22 males, 12 females; age 36.0?±?11.3 years) including 20 with LGGs and 14 with HGGs, all scanned on a 3T MR scanner. Only tumours without intense CE were included. Two neuroradiologists independently performed histogram analyses to measure the 90th-percentile (APT90) and mean (APTmean) of the tumours’ APT signals. The apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) were also measured. The parameters were compared between the groups with Student’s t-test. Diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis.

Results

The APT90 (2.80?±?0.59 % in LGGs, 3.72?±?0.89 in HGGs, P?=?0.001) and APTmean (1.87?±?0.49 % in LGGs, 2.70?±?0.58 in HGGs, P?=?0.0001) were significantly larger in the HGGs compared to the LGGs. The ADC and rCBV values were not significantly different between the groups. Both the APT90 and APTmean showed medium diagnostic performance in this discrimination.

Conclusions

APT imaging is useful in discriminating HGGs from LGGs among diffuse gliomas without intense CE.

Key Points

? Amide proton transfer (APT) imaging helps in grading non-enhancing gliomas ? High-grade gliomas showed higher APT signal than low-grade gliomas ? APT imaging showed better diagnostic performance than diffusion- and perfusion-weighted imaging
  相似文献   
76.
Brain tumors harbor various BRAF alterations, the vast majority of which are the BRAF kinase‐activating V600E mutation. BRAF mutations are most frequently detected in certain subtypes of low‐grade glioma, such as pilocytic astrocytoma (PA), pleomorphic xanthoastrocytoma (PXA), ganglioglioma (GG) and dysembryoplastic neuroepithelial tumor (DNT). However, it is unclear whether gliomas harboring BRAF mutations can be invariably regarded as these glioma subtypes or their derivatives. To address this question, we analyzed 274 gliomas in our institutional case series. We performed high‐resolution melting analyses and subsequent direct Sanger sequencing on DNA isolated from snap‐frozen tumor tissues. As expected, BRAF mutations were detected in the aforementioned low‐grade gliomas: in 4/27 PAs, 2/3 PXAs, 4/8 GGs, and 1/6 DNTs. In addition to these gliomas, 1/2 astroblastomas (ABs) and 2/122 glioblastomas (GBs) harbored BRAF mutations. Pathological investigation of the two GBs revealed that one was a GB displaying epithelial features that presumably arose from a precedent GG, whereas the other GB, which harbored a rare G596 A mutation, showed marked epithelial features, including astroblastic rosettes. Our results indicate that in addition to being present in established BRAF‐associated gliomas, BRAF mutations might be associated with epithelial features in high‐grade gliomas, including sheet‐like arrangement of polygonal tumor cells with a plump cytoplasm and astroblastic rosettes, and thus could potentially serve as a genetic marker for these features.  相似文献   
77.
The present study employed enzyme-immunoassay to examine the effect of ethanol on endothelin-1 and/or -2(ET1 + 2) release from human umbilical vein endothelial cells. Thirty minutes of exposure to ethanol increased the release of immunoreactive ET1 + 2 from cultured endothelial cells in a dose-dependent manner. However, ethanol at concentrations of less than 400 mM did not induce any LDH release from the endothelial cells. Trypan blue exclusion test revealed that 400 mM solution of ethanol decreased the cell viability to 7.7%. Thus, ethanol was found to directly stimulate ET1 + 2 release from cultured human umbilical vein endothelial cells. This reaction of vascular endothelial cells against ethanol may be related to ethanol-induced cardiovascular diseases such as hypertension, myocardial infarction and stroke, as well as fatal alcohol syndrome.  相似文献   
78.
We report the case of a 53‐year‐old woman with a gastrointestinal stromal tumor (GIST) of the duodenum that showed only extramural growth, mimicking a pancreatic tumor. Preoperatively, computed tomography (CT) and angiography revealed a hypervascular mass, 3.0 cm in diameter, in the pancreatic head. Hypotonic duodenography showed compression of the second and third portions of the duodenum by the pancreatic lesion. Endoscopic examination showed no specific mucosal abnormalities in the duodenal lumen. The pancreatic head tumor was diagnosed preoperatively as a nonfunctioning islet cell tumor of the pancreas, and the patient underwent pylorus‐preserving pancreaticoduodenectomy. A hard mass was palpated intraoperatively in the pancreatic head region, and neither peritoneal dissemination nor metastasis was detected. Histologically, the tumor was composed of spindle‐shaped cells with a fascicular growth pattern, and only a few mitotic features were seen. Immunohistochemically, most of the tumor cells were positive for c‐kit oncoprotein and CD34, but negative for alpha‐smooth muscle actin and S‐100 protein. Therefore, this neoplasm was finally diagnosed as a duodenal GIST of the uncommitted type. This is a rare case of a duodenal GIST with exclusively extramural growth mimicking a pancreatic head tumor.  相似文献   
79.
80.

Aim

The enhanced liver fibrosis (ELF) test is a noninvasive method for diagnosing hepatic fibrosis in patients with nonalcoholic fatty liver disease (NAFLD). This multicenter cohort study aimed to evaluate the accuracy of the ELF test and compare it with other noninvasive tests in Japan.

Methods

We analyzed 371 Japanese patients with biopsy-proven NAFLD. We constructed area under the receiver operator characteristic curves (AUROC) to determine the diagnostic accuracies of the ELF test, the Mac-2-binding protein glycosylation isomer (M2BPGi), the Fibrosis-4 (FIB-4) index, and combinations of these indices.

Results

In patients with F0/F1/F2/F3/F4 fibrosis, the median values of the ELF test were 8.98/9.56/10.39/10.92/11.41, respectively. The AUROCs of the ELF test for patients with F0 versus F1–4, F0–1 versus F2–4, F0–2 versus F3–4, and F0–3 versus F4 fibrosis were 0.825/0.817/0.802/0.812, respectively. The AUROCs of the ELF test were greater than those of the FIB-4 index and M2BPGi at each fibrosis stage. Respective low and high cut-off values yielded sensitivities and specificities for predicting advanced fibrosis (≥F3) of 91.1% and 50.8%, and 38.5% and 92.8%, respectively. For F3 or F4 fibrosis, the combined values from the ELF test and FIB-4 index showed a sensitivity of 98.5%, and the combined values from the ELF test and M2BPGi assay showed a specificity of 97.5%.

Conclusions

In Japan, the ELF test predicts NAFLD-related fibrosis from its early stages. The diagnostic ability of the ELF test was not inferior to that of other indices, and the combined values of ELF plus other indices were more accurate.  相似文献   
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