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51.
BACKGROUND/AIMS:: To clarify the mechanism of excess hepatic iron accumulation in chronic hepatitis C, we investigated the expressions of transferrin receptor 1 and divalent metal transporter 1 in hepatocytes, both of which are involved in cellular iron uptake, in relation to the degree of hepatic iron accumulation and hepatic fibrosis by immunohistochemistrical study. METHODS:: Forty-six hepatic tissues with chronic hepatitis C and five normal hepatic tissues were examined. Chemical detection of hepatic iron accumulation was performed by Perl's Prussian blue stain. The immunohistochemistrical study was performed by avidin-biotin complex method with alkaline phosphatase. RESULTS:: In chronic hepatitis C: (1) Hepatic iron accumulation was significantly increased in relation to the advance of the fibrosis. (2) Divalent metal transporter 1 decreased significantly in relation to the advance of hepatic fibrosis. (3) Transferrin receptor 1 expression was always detected, although not in normal hepatic tissues; there was no relation between expression levels and the degree of hepatic fibrosis. CONCLUSIONS:: These data demonstrated that the transferrin receptor 1 expression was up-regulated irrespective of the degree of hepatic iron accumulation, suggesting that the up-regulation of transferrin receptor 1 might act as one of the key mechanisms implicated in the accumulation of hepatic iron in chronic hepatitis C.  相似文献   
52.

Background

Atopic dermatitis (AD) is exacerbated by sweating, and the skin of most patients with AD are resided by Malassezia (M.) fungi. Recently, MGL_1304 produced by Malassezia globosa was identified as the major histamine releasing antigen in human sweat.

Methods

The full length cDNA of the counterpart of MGL_1304 in Malassezia restricta (Mala r 8), was cloned by degenerate PCR and rapid identification of cDNA ends (RACE). Recombinant MGL_1304, and its counterparts, Mala s 8 (produced by Malassezia sympodialis) and Mala r 8 were prepared, and compared in their allergenicities by dot blot analysis and histamine release tests with sera and basophils of patients with AD.

Results

The identities between MGL_1304 and Mala s 8, MGL_1304 and Mala r 8, and Mala s 8 and Mala r 8 were 68%, 78%, and 76%, respectively, in protein sequences. Dot blot analysis revealed that the level of IgE binding to Mala s 8 was higher than that of MGL_1304. However, histamine release tests revealed that MGL_1304 and Mala r 8 possessed higher activity than Mala s 8. In addition, the crude lysate of M. globosa showed higher histamine release ability than that of M. sympodialis.

Conclusions

Patients with AD showed hypersensitivities against MGL_1304 and its homologs. However, the allergenicities of the homologs are variable and the histamine release activities may be different from the solid-phase binding activities for IgE. Sweat allergy should be carefully evaluated with biological activities of MGL_1304 and its homologs of other Malassezia fungi residing on the skin.  相似文献   
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A patient with acute myelogenous leukemia developed prolonged bone marrow failure along with the monosomy 7 chromosome abnormality. The patient had undergone bone marrow transplantation with CD34+ selection following induction failure. However, she then suffered engraftment failure and long-term pancytopenia. Her white blood cell count gradually increased with supportive therapy including granulocyte colony-stimulating factor (G-CSF), and chromosomal analysis of bone marrow cells revealed an abnormal karyotype. Thirty months after the bone marrow transplantation we observed monosomy 7 together with the existing chromosomal abnormality in the patient's bone marrow cells. It has been reported that some patients with idiopathic and posthepatitis aplastic anemia develop clonal disorders such as myelodysplastic syndrome/acute myelogenous leukemia with monosomy 7. The findings in our case suggest that the appearance of monosomy 7 in patients with aplastic anemia may be caused by prolonged low-level hematopoiesis, with or without G-CSF stimulation.  相似文献   
55.
For patients with a history of heparin-induced thrombocytopenia (HIT) who undergo cardiac or vascular surgery, the optimal anticoagulation substitute for heparin has yet to be established. Recombinant hirudin has been recommended; however, this agent is unsuitable for patients with renal dysfunction. Argatroban was used in the present patient who had a history of HIT and renal dysfunction and required peripheral vascular surgery. Argatroban was easy to monitor and control, regardless of renal function, and has advantages over other anticoagulants for such patients.  相似文献   
56.
Multiple myeloma (MM) is a plasma‐cell neoplasm that can cause renal disorders. Renal lesions in MM can present with a very rare pathological manifestation involving a specific monoclonal immunoglobulin (Ig). We report the case of a 33‐year‐old woman who had edema, fatigue, elevated serum creatinine levels, hypoalbuminemia, and hypercholesterolemia. She had persistent hematuria and proteinuria lasting 3 years. Serum protein electrophoresis showed an M‐spike, and serum immunofixation demonstrated the presence of monoclonal IgG λ. She had proteinuria in the nephrotic range, and a monoclonal λ fragment was present on urine immunofixation. Renal biopsy showed proliferative glomerulonephritis with λ light chain and C3c deposition and inflammatory cell infiltration with CD68. Macrophage lysosomes contained λ light chains, suggesting their partial phagocytosis. She was diagnosed with symptomatic MM and was treated with bortezomib and dexamethasone and an autologous peripheral stem cell transplant conditioned with intravenous melphalan. She achieved a partial response with decreased serum monoclonal protein and improved renal function. This case may be categorized as a monoclonal gammopathy‐associated proliferative glomerulonephritis. The biopsy finding of partially phagocytosed Ig λ light chains by macrophages is very rare; this pathological condition is similar to crystal‐storing histiocytosis.  相似文献   
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A 47-year-old Japanese man was referred to our hospital because of a sustained high fever with diarrhea 12 days after a flight from India. Liver enzymes were elevated with rose spots, hepatosplenomegaly, relative bradycardia, and acute cholecystitis. A liver biopsy depicted the dense infiltration of lymphocytes and Kupffer cells in sinusoids and the granulomatous formation in the parenchyma. The liver damage was initially resolved with the administration of ceftriaxone for 16 days but flared up 1 week later. Laboratory tests yielded positive reactions for Salmonella typhi and hepatitis E virus RNA. The pathophysiological presentations of concurrent typhoid and type E hepatitis are discussed.  相似文献   
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