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91.
Cronkhite-Canada syndrome (CCS) is a rare polyposis disorder accompanied by alopecia and onychodystrophy. A 63-year-old man with a history of CCS and repeated embolism developed progressive thrombocytopenia and mild anemia. Laboratory testing, a bone marrow examination, and magnetic resonance imaging of the spine resulted in a diagnosis of concurrent aplastic anemia (AA). Paroxysmal nocturnal hemoglobinuria (PNH)-type cells were detected in a peripheral blood specimen. In addition, human leukocyte antigen (HLA) included DRB1*15:01 and DRB1*15:02. Mesalazine was discontinued in consideration of possible drug-induced pancytopenia. Immunosuppressive therapy ameliorated both the gastrointestinal symptoms of CCS and pancytopenia. A common autoimmune abnormality might underlie both CCS and AA.  相似文献   
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93.
Hyperglycemia increases oxidative stress in various tissues and leads to diabetic cardiovascular complication. Dyslipidemia, such as an increase in oxidized low-density lipoprotein (LDL), is well recognized in diabetic patients with hyperglycemia. However, the mechanism by which hyperglycemia causes the increased LDL oxidation remains unclear. Albumin is the most abundant protein in the circulation, and can function as an antioxidant. Therefore, we examined whether glycoxidative modification inhibits the antioxidant activity of albumin to LDL oxidation and clarified the mechanism by which this modification may suppress its antioxidant activity. Human serum albumin (HSA) was incubated in phosphate-buffered saline with and without glucose at 37°C for up to 8 weeks under aerobic conditions (referred to as glycoxidation (goHSA) and oxidation (oHSA), respectively). Metal chelator-treated, nonoxidative HSA (chHSA) and freshly prepared HSA (fHSA) were used as controls. N ε-(carboxymethyl)lysine (CML), a glycoxidative product, was determined by enzyme-linked immunosorbent assay. Oxidation was estimated by measuring the thiols of the HSA molecule. Copper-mediated oxidation of LDL was conducted in the presence or absence of modified HSAs at 37°C for 6 days. Malondialdehyde and negative charge of LDL were measured. To clarify the mechanism of reduced antioxidant activity of HSA, we examined firstly the binding activity of modified HSAs to copper, and secondly the effects of free radical scavengers on the formation of malondialdehyde. CML was formed in goHSA in a time- and concentration-dependent manner. Both goHSA and oHSA significantly decreased the contents of free thiol groups compared to ch- and fHSAs. The antioxidant activity of goHSA to LDL oxidation was the lowest among various modified HSAs. The oHSA showed a moderate decrease in antioxidant activity. The binding activity of go- and oHSAs to copper was lower than that of ch- and fHSAs. The formation of MDA from LDL oxidation in the presence of goHSA was completely inhibited by Tiron (1,2-dihydroxy-3,5-benzenedisulfonic acid) and superoxide dismutase. In contrast, catalase and mannitol had no effect. Our results indicate that in vitro glycoxidation of HSA induced a marked loss of antioxidant activity of this molecule to copper-mediated oxidation of LDL, which may be caused by the generation of superoxide. Received: December 17, 2001 / Accepted: June 28, 2002 Acknowledgments The authors thank Drs. Ryoji Nagai and Seikoh Horiuchi (Department of Biochemistry, Kumamoto University School of Medicine, Kumamoto, Japan) and Drs. Hiroyuki Itabe and Tatsuya Takano (Department of Microbiology and Molecular Pathology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa, Japan) for kindly supplying antibodies. We also thank Associate Professor Takeo Yamaguchi (Department of Chemistry, Faculty of Science, Fukuoka University) for the ESR experiment and Miss Satoko Nagano for her excellent technical assistance. This work was supported by a Grant-in-Aid from the Ministry of Education, Science, Sports and Culture of Japan (No. 14570171) and in part by funds from the Central Research Institute of Fukuoka University (No. 016004). Correspondence to N. Sakata  相似文献   
94.
Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) ( n  = 26), nodular (N) ( n  = 11), D + N ( n  = 13) or normal (n) ( n  = 11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.  相似文献   
95.
The mechanisms that are responsible for the development of myocardial fibrosis in inflammatory cardiomyopathy are unknown. We have previously generated lines of transgenic mice with cardiac-restricted overexpression of tumor necrosis factor (MHCsTNF mice), a pro-inflammatory cytokine. The MHCsTNF mice develop a heart failure phenotype that is characterized by progressive myocardial fibrosis, as well as increased levels transforming growth factor-β (TGF-β)(mRNA and protein. In order to determine whether TGF-β-mediated signaling was responsible for the myocardial fibrosis observed in the MHCsTNF mice, we treated MHCsTNF and littermate control mice from 4 to 12 weeks of age with a novel orally available TGF-β receptor antagonist (NP-40208). At the time of terminal study, myocardial collagen content was determined using the picrosirius red technique, and left ventricular (LV) systolic and diastolic function were determined using the Langendorff method. Treatment with NP-40208 resulted in a significant (P < 0.05) 65% decrease in nuclear translocation of Smad 2/3, a significant (P < 0.05), decrease in the heart-weight to body-weight ratio from 6.5 to 5.7, a ∼37% decrease in fibrillar collagen content (P < 0.01) and a significant (P < 0.05) decrease in the LV chamber stiffness by ∼25% in the MHCsTNF mice when compared to diluent-treated controls. Treatment with NP-40208 had no discernable effect on LV systolic function, nor any effect on cardiac myocyte size or fetal gene expression in the MHCsTNF mice. Taken together, these observations suggest that sustained pro-inflammatory signaling in the adult heart is associated with a pro-fibrotic phenotype that arises, at least in part, from TGF-β-mediated signaling, with resultant activation of Smad 2/3, leading to increased myocardial fibrosis and increased LV diastolic chamber stiffness. Returned for 1. revision: 29 August 2007 1. Revision received: 24 September 2007  相似文献   
96.
Tissue damage in leptospirosis has been ascribed to direct effect of the microorganisms and/or their virulence, including products synthetized by leptospires or released during their lysis. This study aimed at chemical extraction of the glycolipoprotein (GLP) from virulent leptospires, production of a rabbit anti-GLP and analysis of its distribution in liver and kidney of inoculated guinea-pigs, sacrificed sequentially from the 1st to 6th day of infection, covering the whole, spectrum of acute leptospirosis. The comparison of GLP expression to local injuries aimed at new pathogenetic data. GLP was detected in liver and kidney in 2 out of 6 guinea-pigs on the 5th day and in all 6 animals on the 6th day of infection. Granular forms were seen in the cytoplasm of macrophages, free in interstitium or adhered to endothelial and parenchymal cell membranes, especially in the most damaged sites. These findings lead us to the hypothesis of GLP as a toxic factor resulting from leptospiral lysis by macrophages. Although it was not proved as a promoter of initial lesions, it seems to be related to the enhancement of tissue damage late in the course of the disease.  相似文献   
97.
98.
Abstract. Genetic polymorphism of human plasminogen in the Japanese population was studied using agarose gel isoelectric focusing followed by immunofixation. A new basic variant, PLG B, was found as a heterozygous state PLG l-B, which was genetically determined. The allele frequencies calculated from 258 individuals were PLG1 =0.958, PLG2 =0.020 and PLGB =0.022.  相似文献   
99.
Pancreatic cancer represents a major challenge to oncologists because of its high chemoresistant nature and dismal outcomes. Conventional therapy for advanced disease relied for a long time on palliative 5‐fluorouracil (5‐FU)‐based chemotherapy, but with unsatisfactory results. The introduction of the novel antimetabolite gemcitabine provides new optimism for patients with advanced pancreatic cancer, as multiple clinical trials have demonstrated the superiority of gemcitabine over 5‐FU and other agents for these patients. The benefits of gemcitabine over conventional therapies include improved response rate and enhanced survival, as well as improvement in disease‐related symptoms and quality of life in these patients. With these data, gemcitabine is widely accepted worldwide as the therapy of choice by many oncologists for advanced pancreatic cancer. The current review presents an overview of the clinical studies of gemcitabine over the past decade for the treatment of patients with advanced pancreatic cancer. Other investigational regimens or uses (e.g., fixed dose‐rate infusion, intraarterial infusion, adjuvant use, chemo‐radiation, etc) are also reviewed.  相似文献   
100.
BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease associated with recurring inflammation of the colorectal mucosa. Recently, cytapheresis has emerged as a new treatment for patients with UC. Removal methods are mainly performed with beads [granulocyte and monocyte/macrophage adsorptive apheresis (GMCAP)] or filters [leukocytapheresis (LCAP)]. Both treatments have been reported to be effective for active UC. There have been few trials, however, comparing the efficacy of GMCAP and LCAP. In this study, we prospectively evaluated the efficacy of LCAP and GMCAP for the treatment of active UC. METHODS: Thirty-nine patients [18 male, 21 female; mean age 38.7 years; duration of disease 6 years; clinical activity index (CAI) >6 points] with moderate-to-severe active UC were randomly assigned to the LCAP (n=21) or GMCAP group (n=17). Adacolumn (cellulose acetate beads; Japan Immunoresearch Laboratories, Takasaki, Japan) for GMCAP and Cellsorba EX (polyethylene phthalate fibers; Asahi Medical Co. Ltd, Tokyo, Japan) for LCAP were used for leukocyte removal. Patients received two sessions of cytapheresis in the first week, followed by four weekly administrations. Steroid doses were tapered if patients achieved clinical improvement. When the CAI score had decreased by 5 points or more, the patient was considered to have improved. RESULTS: Thirteen patients in the GMCAP group and 14 in the LCAP group achieved clinical improvement. No significant difference was found in clinical response and clinical course between LCAP and GMCAP. Hemoglobin levels were significantly decreased immediately after one session of cytapheresis in the LCAP group. No severe adverse effects were observed in any of the patients. No significant differences were observed in any clinical parameters predictive of a response to either LCAP or GMCAP. But in all patients receiving cytapheresis, a high CAI score was a significant risk factor for treatment failure. All of the cytapheresis nonresponders had CAI scores >or=16. CONCLUSION: Both GMCAP and LCAP were effective treatments for active UC. Patients with severe UC and a high CAI score were, however, refractory to treatment.  相似文献   
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