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201.
A case of solitary neurofibroma in the retroperitoneum involving the uncinate process of the pancreas, which has been reported in only one case in Japan and less than 20 cases in the world literature, is described. A 57-year-old male complained of back pain and microhematuria. Plain and enhanced abdominal computed tomography (CT) indicated an 8 × 6 cm hypovasular tumor located in the uncinate process. We initially assumed it to be a cancer of the pancreas. His physical examination and blood chemistry result were normal. Various diagnostic imaging methods however, disclosed a rare type of tumor. The tumor was resected by pancreaticoduodenectomy and histological examination revealed it to be neurofibroma.  相似文献   
202.
203.
The involvement of radical stress has been suggested as a cause for complications in patients on dialysis, such as arteriosclerosis, dialysis-related amyloidosis, etc. It has been reported that the increase in radical stress is not only seen in renal failure, but that its amplified effect is also seen in the process of blood purification. Our group has reported on the radical stress-reducing effect of HDF. We performed four types of blood purification (HD; on-line HDF; pre, on-line HDF; post, P/P HDF) in patients on maintenance dialysis using the polysulfone (APS) dialyzer. The change in radical related markers such as pentosidine (total, free) and CML (total, free), and the CTL/Cr ratio, and the hydroperoxide radicals were studied. In HDF (post, pre), the amplification rate of hydroperoxide radicals was significantly low, whereas the reduction rate of CTL/Cr ratio as index for hydroxy radicals was significantly higher in on-line HDF than in HD. Both the total CML and T-pentosidine increased in HD but showed a decrease in HDF. As HDF uses large amounts of replacement solution, the following effects can be expected: (a) suppression of the amplification of hydroperoxide radicals and suppression of the amplification of hydroxy radicals, and (b) suppression of fat oxidation by AGEs themselves. These antiradical stress effects are presumed to be exerted by effective removal of radical carrier protein, denatured protein, and complement protein in HDF, by dilution of radicals by massive use of replacement solution, and by the sequential reduction of the excitation and amplification effects.  相似文献   
204.
A 55-year-old woman visited our hospital for further examination of abnormal shadows on chest radiographs. Her routine chest radiograph showed two nodular shadows in the right lower lung field. A chest CT scan revealed other nodules, small patchy shadows in both lung fields, and enlargement of the mediastinal lymphnodes (#2, 3). Laboratory data showed polyclonal hyperimmunoglobulinemia. This case was initially considered on the basis of a transbronchial lung biopsy to be a plasma cell granuloma. However, serum gammaglobulin levels gradually increased, and video-assisted thoracoscopic surgery was performed to aid in making a definite diagnosis. Biopsy specimens revealed lymphoid follicles with plasma cells which were stained with both anti-kappa chain and anti-lambda chain antibodies. The patient was treated with prednisolone (50 mg/day), and the serum gammaglobulin level and the shadows on the chest CT were temporarily slightly improved. During the clinical course, her laboratory data and histological specimens were re-examined, and the final diagnosis was multicentric Castleman's disease.  相似文献   
205.
STUDY OBJECTIVE: To test the hypothesis that haplotypes of the interleukin (IL)-10 gene are associated with clinical outcomes, comparing critically ill patients with sepsis from pneumonia vs those with extrapulmonary sepsis. DESIGN: Genetic association study. SETTING: Medical/surgical ICUs in a tertiary-care, university-affiliated teaching hospital. PATIENTS: Of 550 white patients with sepsis, 158 had pneumonia as the principle cause of their sepsis and 392 had an extrapulmonary source of sepsis. MEASUREMENTS: Haplotypes of the IL-10 gene were defined by measurement of haplotype tag single-nucleotide polymorphisms (SNPs). Primary outcome was 28-day survival. Secondary outcomes were days alive and free of organ dysfunction. RESULTS: Three SNPs in the IL-10 gene (-592 C/A, +734 G/T, and +3367 G/A) identified four major haplotypes: CGG, AGG, CTA, and CTG. Patients with pneumonia who carried one or two copies of the CGG haplotype had greater 28-day mortality (51.4%) than patients who did not carry this haplotype (29.1%, p = 0.007). Carriers of CGG had significantly more cardiovascular dysfunction (and use of vasopressors), renal dysfunction (and requirement of dialysis), hepatic dysfunction, and hematologic dysfunction (p < 0.05 in each case). In contrast, in patients with an extrapulmonary source of infection there was no significant association of the CGG haplotype (or any measured IL-10 genotype) with 28-day mortality or organ dysfunction. CONCLUSIONS: The IL-10 haplotype - 592C/734G/3367G is associated with increased mortality and organ dysfunction in critically ill patients with pulmonary sepsis but not in similarly ill patients with extrapulmonary sepsis. Therefore, polymorphisms within the IL-10 gene may be predictors of outcome in patients with sepsis from pneumonia.  相似文献   
206.
Ursodeoxycholic acid: Mechanism of action and novel clinical applications.   总被引:2,自引:0,他引:2  
Ursodeoxycholic acid (UDCA) is used in the treatment of cholestatic liver diseases, gallstone dissolution, and for patients with hepatitis C virus infection to ameliorate elevated alanine aminotransferase levels. The efficacy of UDCA treatment has been debated and the mechanisms of action in humans have still not defined. Suggested mechanisms include the improvement of bile acid transport and/or detoxification, cytoprotection, and anti-apoptotic effects. In this review, we summarize the proposed molecular mechanisms for the action of UDCA, especially in hepatocytes, and also discuss the putative future clinical usage of this unique drug.  相似文献   
207.
It is well known that squamous carcinomasfrequently develop multifocally, either synchronously ormetachronously, in the upper aerodigestive tract (1).Such phenomena were first reported by Slaughter et al in 1953, and they were named fieldcancerization (2). Using recent molecular biologytechniques, these multiple carcinomas have been revealedto arise from independent origins (3). Esophagealcarcinomas have been reported to frequently metastasize tothe lymph nodes even at the early stage of tumorextension (4). Furthermore, simultaneous multifocalcancer development is not rare in the esophagus (5). In cases of intraesophageal multiple carcinomaswith lymph node metastases, the primary focus of themetastatic tumors cannot be identified by conventionalhistologic examination. Here we report a case of intraesophageal multiple carcinomas in whichthe attributed foci of lymph nodal metastases could beclearly identified by analyzing the p53 gene mutationalstatus used as a clonal marker.  相似文献   
208.
Background and objective:   While recent studies have shown that patients with COPD and patients with asthma exhibit evidence of airway and systemic inflammation, markers of systemic inflammation have not been compared between the two diseases.
Methods:   To evaluate circulating inflammatory markers, blood was sampled from 111 patients with COPD, 75 control subjects and 46 asthmatic patients (some of whom were smokers). Measurements of WCC, serum levels of fibrinogen, high-sensitivity (hs)-CRP, IL-8, IL-6, tumour necrosis factor-α (TNF-α), transforming growth factor (TGF)-β1, tissue inhibitors of metalloproteinase (TIMP)-1, neutrophil elastase and alpha1-antitrypsin (α1-AT) were performed.
Results:   Serum TNF-α, IL-6 and TIMP-1 concentrations were significantly higher in patients with stable COPD and patients with asthma than in control patients. Serum α1-AT levels were significantly higher in COPD patients than in asthmatic patients and control subjects, and serum TGF-β1 levels were higher in asthma patients than in COPD patients. Smoking status had no effect on markers in COPD and asthmatic patients.
Conclusions:   Although COPD and asthma share common markers of systemic inflammation, serum levels of TGF-β1 and α1-AT may reflect differences between the diseases.  相似文献   
209.
Both hypoxia and interleukin-17A (IL-17A) promote the migration and invasion of fibroblast-like synoviocytes (FLSs), which are critical for the pathogenesis of rheumatoid arthritis (RA). However, the biochemical pathways regulating IL-17A combined with hypoxia are not well defined. In this study, we found that co-stimulating RA-FLSs with IL-17A and hypoxia did not appear to promote the epithelial–mesenchymal transition (EMT), but did increase cell motility. We further showed that a proinvasive effect of IL-17A on FLSs under hypoxia might be through upregulation of matrix metalloproteinase 2 (MMP2) and MMP9. Moreover, IL-17A-induced expression of MMP2 and MMP9 under hypoxia was accompanied by increased activation of nuclear factor-κB (NF-κB)/hypoxia-inducible factor-1α (HIF-1α). Knockdown or inhibition of HIF-1α and NF-κB by small interfering RNA or specific small molecule inhibitors blocked IL-17A-mediated and hypoxia-mediated MMP2 and MMP9 expression, cell migration, and invasion. In addition, the inhibition of NF-κB led to a marked decrease in the expression of HIF-1α, which indicated that IL-17A activated HIF-1α via the NF-κB pathway in hypoxia. Taken together, our observations suggest a synergetic effect of IL-17A and hypoxia that might contribute to the migration and invasion of RA-FLSs by upregulating the expression of MMP2 and MMP9 by activation of the NF-κB/HIF-1α pathway.  相似文献   
210.
Cathepsin is a typical and well-characterized lysosomal cysteine protease that, under pathological conditions, is involved in tissue destruction. A recent immunocytochemical study demonstrated that cathepsins B (CAB) and L (CAL) were localized in the periodontal ligament (PDL) of the rat molar, and they were expressed in compressed sites during experimental tooth movement. Further, we demonstrated previously that the levels of CAB and CAL in gingival crevicular fluid increased during orthodontic tooth movement. Therefore, CAB and CAL may play important roles in the process of collagen degradation during orthodontic tooth movement, and our in vitro study examined the secretion of CAB and CAL in PDL cells following mechanical stress. PDL cells were subjected to 0.5, 1.0, 2.0, or 3.0 g/cm2 of compression force or an increase in surface area by tension force of 0.28%, 0.95%, 1.72%, or 2.50% for 24 hr. For detection of CAB and CAL in conditioned medium, commercially available ELISA kits were used. We found compression and tension significantly increased the secretions of both CAB and CAL in PDL cells, which were exhibited in a time- and force magnitude-dependent manner. The compression-stimulated secretion of CAB was increased approximately 3-fold and that of CAL 4-fold, as compared with the control. Further, tension-stimulated secretion of CAB was increased by 1.5-fold and that of CAL 2-fold compared with the control. When analyzed using a semiquantitative polymerase chain reaction assay, CAB and CAL mRNA were increased in response to both compression and tension forces. These findings demonstrated that mechanical stress (compression and tension forces) causes an increase in secretion of CAB and CAL in PDL cells in vitro.  相似文献   
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