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51.
A method for correctly assessing hydroxyl radical scavenging activity of antioxidative chemicals and/or biological compounds/materials was proposed. This method can simultaneously assess two factors, i.e. hydroxyl radical-scavenging and 5,5-dimethyl-2-hydroxy-1-pyrrolidine-N-oxide (hydroxyl radical adduct of 5,5-dimethyl-1-pyrroline-N-oxide)-reducing ability, as antioxidative properties. In this paper, some biologically common hydrophilic molecules, cell culture media, and rat plasma were tested. X-ray-induced hydroxyl radical can be detected using the electron paramagnetic resonance spin trapping technique. Using X-ray irradiation of the reaction mixture as the hydroxyl radical source, the true hydroxyl radical-scavenging ability of the subjected antioxidant can be assessed. In addition, the method simultaneously measures the reduction of 5,5-dimethyl-2-hydroxy-1-pyrrolidine-N-oxide, to estimate the reducing ability of the antioxidant. Biological materials, such as sugars and proteins, could abolish hydroxyl radical at the biological concentration. Ascorbic acid showed reducing ability at the biological concentration. The simultaneous assessment of hydroxyl radical-scavenging and reducing ability of antioxidants can be an informative index for antioxidants.  相似文献   
52.
Cryopyrin-associated periodic syndrome (CAPS) is a spectrum of systemic autoinflammatory disorders in which the majority of patients have mutations in the cold-induced autoinflammatory syndrome (CIAS)1 gene. Despite having indistinguishable clinical features, some patients lack CIAS1 mutations by conventional nucleotide sequencing. We recently reported a CAPS patient with mosaicism of mutant CIAS1, and raised the possibility that CIAS1 mutations were overlooked in "mutation-negative" patients, due to a low frequency of mosaicism. To determine whether there were latent mutant cells in "mutation-negative" patients, we sought to identify mutation-associated biologic phenotypes of patients' monocytes. We found that lipopolysaccharide selectively induced necrosis-like cell death in monocytes bearing CIAS1 mutations. Monocyte death correlated with CIAS1 up-regulation, was dependent on cathepsin B, and was independent of caspase-1. Cell death was intrinsic to CIAS1-mutated monocytes, was not mediated by the inflammatory milieu, and was independent of disease severity or anti-IL-1 therapy. By collecting dying monocytes after lipopolysaccharide treatment, we succeeded in enriching CIAS1-mutant monocytes and identifying low-level CIAS1-mosaicism in 3 of 4 "mutation-negative" CAPS patients. Our findings reveal a novel effect of CIAS1 mutations in promoting necrosis-like cell death, and demonstrate that CIAS1 mosaicism plays an important role in mutation-negative CAPS patients.  相似文献   
53.

Objectives  

Decompression of the median nerve in the area of the pronator teres.  相似文献   
54.
PURPOSE: To compare a multishot echo-planar fluid-attenuated inversion-recovery (EPI-FLAIR) sequence with fast spin-echo FLAIR (F-FLAIR) and fast spin-echo T2-weighted (FSE-T2W) sequences in depiction of white matter lesions. METHODS: Thirty-five patients with various white matter lesions were included in this prospective study. Two independent readers for lesion detection (lesion size, >2 mm) compared sequences quantitatively. In 22 patients, contrast was calculated between periventricular hyperintensity (PVH) and the cerebrospinal fluid (CSF). RESULTS: EPI-FLAIR revealed more lesions than FSE-T2W (p < 0.01). However, F-FLAIR revealed more lesions than EPI-FLAIR (p < 0.01). For PVH-to-CSF contrast, EPI-FLAIR demonstrated significantly higher contrast than FSE-T2W. There were no differences in PVH-to-CSF contrast between EPI-FLAIR and F-FLAIR. CONCLUSIONS: This study shows that EPI-FLAIR has distinct advantages over FSE-T2W in the depiction of white matter lesions. Although EPI-FLAIR reduces imaging time by more than 60% relative to F-FLAIR, it cannot replace F-FLAIR for the detection of lesions in the cerebral white matter.  相似文献   
55.
Postoperative superior mesenteric artery syndrome is a rare complication of left nephrectomy. We treated a case of superior mesenteric artery syndrome that occurred 7 days after radical left nephrectomy for renal cell carcinoma. The patient was a 54-year-old Japanese man who presented with gross hematuria. Abdominal computed tomography showed a 3.8 x 3.8 x 5 cm heterogeneous cystic mass in the left kidney. Transperitoneal left radical nephrectomy was performed because renal cell carcinoma was suspected. The patient resumed oral intake 3 days after surgery, but he began vomiting repeatedly from the 7th day after surgery. Gastroduodenography showed an abrupt vertical linear obstruction of the third portion of the duodenum. Superior mesenteric artery syndrome was diagnosed. Conservative therapy (indwelling nasogastric tube, intravenous hyperalimentation and postural changes) was effective.  相似文献   
56.

Background context

Localized amyloid deposits result in a mass, that is, so-called amyloidoma; it has been reported in every anatomic site, although systemic amyloid deposition is much more common. However, primary lumbar epidural amyloidoma without bony involvement is extremely rare. To the best of our knowledge, only one case has been reported previously.

Purpose

To report and review the clinical presentations, imaging studies, and treatment of epidural and paravertebral amyloidoma.

Study design

A case report and review of the literature.

Methods

Lumbar epidural and paravertebral amyloidoma in a 75-year-old man with neurologic compromise is presented. Laminectomy with mass resection was performed.

Results

After surgery, almost complete neurologic improvement was observed. Histologically, definite diagnosis was obtained only after the specific staining of tissue. No sign of local recurrence was evident 1 year after surgery.

Conclusions

Primary amyloidoma, although rare, should be included in the differential diagnosis of epidural mass of the spine. Diagnosis before surgery is difficult as there were no characteristic findings in clinical and imaging studies. Special histologic technique and stains are useful to make a definite diagnosis.  相似文献   
57.
In this study, we examined the effects of overexpression of SIRT1 on IL‐1β‐induced gene expression changes in human chondrocytes to explore a protective role of SIRT1 in human chondrocytes. SIRT1 was overexpressed in human chondrocytes by expression plasmid under stimulation with IL‐1β. SIRT1 was also inhibited by siRNA under stimulation with IL‐1β. Gene expression changes were examined by real‐time PCR. The interaction of SIRT1 and p65 (NF‐κB) were examined by Western blotting. SIRT1, MMP‐13, and ADAMTS‐5 expressions in human cartilage were examined by immunohistochemistry. IL‐1β stimulation significantly up‐regulated MMP‐1, 2, 9, and 13 and ADAMTS‐5. Overexpression of SIRT1 significantly inhibited the up‐regulation of those genes caused by IL‐1β while the inhibition of SIRT1 further increased them. In addition, the overexpression of SIRT1 markedly reduced the IL‐1β‐induced acetylation of p65. SIRT1 expression was clearly detected in the non‐OA cartilage while MMP‐13 and ADAMTS‐5 were undetectable. In contrast, in the OA cartilage, SIRT1 expression was decreased while MMP‐13 and ADAMTS‐5 were increased. Our observations suggested that SIRT1 can play a protective role by suppressing IL‐1β‐induced expressions of cartilage‐degrading enzymes partially through the modulation of the NF‐κB pathway. SIRT1 overexpression might be a new therapeutic approach for OA. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 531–537, 2013  相似文献   
58.
We report a case of intestinal obstruction caused by metastasis that manifested 6 years after surgery for intrahepatic cholangiocarcinoma (ICC). The patient, a 57-year-old man, had undergone resection of the hepatic left lobe, Spiegel lobe, and extrahepatic bile duct, following which histopathological examination had confirmed the diagnosis of ICC and that the resection margins were free from disease. There had been no signs of recurrence until an increase in the CA19-9 level was detected 6 years later. Colonoscopy revealed an ulcer-like lesion and stenosis at the level of the hepatic flexure. The patient was subsequently admitted to our hospital with abdominal pain and underwent right hemicolectomy with partial resection of hepatic segment V. Based on the immunohistological finding that the expression pattern of cytokeratins and mucins was consistent with ICC origin rather than colon cancer origin, we diagnosed colon metastasis from ICC.  相似文献   
59.
We successfully operated a patient with Crawford type II dissecting thoracoabdominal aortic aneurysm using deep hypothermic circulatory arrest and continuous proximal aortic perfusion. A 70-year-old male who had a history of chronic Stanford type B aortic dissection treated by Y-graft replacement of the abdominal aorta 2 years ago underwent dissecting thoracoabdominal aotic aneurysm repair due to expansion of the aneurysm. A preoperative examination revealed 90% stenosis in his coronary system. We used deep hypothermic circulatory arrest (bladder temperature: 22 degrees C) and continuous proximal aortic perfusion as adjuncts to prevent organ malperfusion (including the coronary arteries) or embolism because sequential aortic clamping seemed impossible and the true lumen became narrowed. To minimize the duration of the extracorporeal circulation (ECC), visceral branches were reattached using a selective shunt after conclusion of ECC. The duration of aortic cross-clamping, ECC, and operation was 170, 302, and 1,020 minutes, respectively. The patient required mechanical ventilation for 12 days but survived the operation and was discharged after 42 days hospitalization without any neurologic sequela. A perioperative intensive treatment must be required to prevent morbidities related to extensive thoracoabdominal aortic aneurysm repair.  相似文献   
60.
A rare abnormality of the A1 segment of the anterior cerebral artery (ACA) is reported. The right ACA bifurcated into two parts at the middle point of the A1 segment, and these segments did not rejoin. The superior right A1 segment connected with the left A1 and formed a single pericallosal artery. The inferior right A1, from which the right ophthalmic artery originated, had no connection with the left A1.  相似文献   
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