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71.
Patients with IgA nephropathy show an emergence of IgA dominant circulating immune complexes (CIC) as well as increased levels of serum IgA and/or IgA bearing peripheral blood lymphocytes. In order to elucidate immunological aberrations responsible for the increased IgA synthesis in such patients, quantitative and qualitative analysis was performed on T alpha cells which have been recently identified as possessing IgA specific helper activity on human B cells. Three different methods were employed to quantitate T alpha cells. These methods included a rosette formation of T cells with either bovine red cells coated with the IgA fraction of anti-bovine red cell antiserum or those coated with TNP and anti-TNP IgA antibody, and an analysis of T cells combined with fluorescein conjugated human IgA myeloma protein. T alpha cells were sorted by a fluorescence activated cell sorter and co-cultured with a B cell rich fraction to evaluate whether there is a qualitative difference in IgA specific helper activity between patients and healthy adults. T alpha cells were significantly increased in patients with IgA nephropathy while there were no significant changes in patients with chronic proliferative glomerulonephritis without mesangial deposition of IgA. There was no qualitative difference in IgA specific helper activity of T alpha cells between patients and healthy adults. It is suggested that increased levels of T alpha cells in patients with IgA nephropathy may be responsible for increased synthesis of IgA in such patients.  相似文献   
72.
A study on the evaluation of staining findings of immunofluorescence in unfixed or fixed renal biopsy specimens is described. Renal biopsy specimens obtained from ten patients with IgA nephropathy and membranous nephropathy were embedded in gelatin or paraffin matrix. Renal biopsy specimens embedded in paraffin matrix were digested with 0.05% protease. The specimens were stained with FITC-conjugated anti-human IgA, IgG, IgM or C3 antisera at 4 degrees C overnight. IgA, IgG or IgM were markedly observed in glomeruli using unfixed materials embedded in gelatin matrix or 10% neutral buffered formalin fixed materials embedded in paraffin matrix from patients with IgA nephropathy and membranous nephropathy. There was no significant difference in the intensity or distribution of IgA, IgG or IgM deposition among the two different conditions of immunofluorescence in patients with such diseases. Although the deposition of IgA using unfixed materials embedded in gelatin matrix was prominently coarse granular or lumpy in glomeruli from patients with IgA nephropathy, that of IgA using 10% formalin fixed materials embedded in paraffin matrix was fine granular and/or interrupted linear in glomeruli. It was suggested that the immunofluorescence in renal biopsy specimens embedded in paraffin matrix after digestion with protease is useful for the evaluation of immunoglobulins in glomeruli from patients with IgA nephropathy or membranous nephropathy.  相似文献   
73.
Migration inhibitory factor (MIF) responds to tissue damage and regulates inflammatory and immunological processes. To elucidate the function of MIF in cutaneous wound healing, we analyzed MIF knockout (KO) mice. After the excision of wounds from the dorsal skin of MIF KO and wild-type (WT) mice, healing was significantly delayed in MIF KO mice compared to WT mice. Lipopolysaccharide treatment significantly increased [(3)H]thymidine uptake in WT mouse fibroblasts compared to MIF KO mouse fibroblasts. Furthermore, there was a significant reduction in fibroblast and keratinocyte migration observed in MIF KO mice after 1-oleoyl-2-lysophosphatidic acid treatment. We subsequently examined whether MIF-impregnated gelatin slow-release microbeads could accelerate skin wound healing. Injection of more than 1.5 microg/500 microl of MIF-impregnated gelatin microbeads around a wound edge accelerated wound healing compared to a single MIF injection without the use of microbeads. MIF-impregnated gelatin microbeads also accelerated skin wound healing in C57BL/6 mice and diabetic db/db mice. Furthermore, incorporating MIF-impregnated gelatin microbeads into an artificial dermis implanted into MIF KO mice accelerated procollagen production and capillary formation. These findings suggest that MIF is crucial in accelerating cutaneous wound healing and that MIF-impregnated gelatin microbeads represent a promising treatment to facilitate skin wound healing.  相似文献   
74.
Correlation of paramesangial deposits ("hemispherical body") and glomerular sclerosis and/or hyalinosis was examined by light microscopical analysis in 40 patients of IgA nephropathy. Correlation of paramesangial deposits and intensity of IgA or C3 deposition in glomeruli was also evaluated in these patients. The number of paramesangial deposits was markedly increased in patients with moderate and advanced stages of IgA nephropathy who showed marked glomerular sclerosis and/or hyalinosis. There was a significant correlation between the number of paramesangial deposits and the intensity of IgA deposits in glomeruli. It is suggested that the accumulation of paramesangial deposits might induce severe glomerular injuries such as glomerular sclerosis and/or hyalinosis.  相似文献   
75.
76.
Nishio M  Nagata A  Tsurudome M  Ito M  Kawano M  Komada H  Ito Y 《Virology》2004,329(2):289-301
The Sendai virus pi strain (SeVpi) isolated from cells persistently infected with SeV shows mainly two phenotypes: (1) temperature sensitivity and (2) an ability of establishing persistent infection (steady state). Three amino acid substitutions are found in the Lpi protein and are located at aa 1088, 1618, and 1664. Recombinant SeV(Lpi) (rSeV(Lpi)) having all these substitutions is temperature sensitive and is capable of establishing persistent infection (steady state). rSeVs carrying the fragment containing L1618V show both phenotypes. rSeV(L1618V), in which leucine at aa 1618 is replaced with valine, has the ability of establishing persistent infection, but is not a temperature-sensitive mutant, indicating that the ability of a virus to establish persistent infection can be separated from temperature sensitivity. The amino acid change at 1618(L-->V) coexisting with aa 1169 threonine is required for acquirement of a temperature-sensitive phenotype. Three amino acid substitutions are also found in the Ppi protein, but rSeV(Ppi) does not show these phenotypes.  相似文献   
77.
78.
Vascular Ehlers–Danlos syndrome (vEDS) is a hereditary connective tissue disorder (HCTD) characterized by arterial dissection/aneurysm/rupture, sigmoid colon rupture, or uterine rupture. Diagnosis is confirmed by detecting heterozygous variants in COL3A1. This is the largest Asian case series and the first to apply an amplification-based next-generation sequencing through custom panels of causative genes for HCTDs, including a specific method of evaluating copy number variations. Among 429 patients with suspected HCTDs analyzed, 101 were suspected to have vEDS, and 33 of them (32.4%) were found to have COL3A1 variants. Two patients with a clinical diagnosis of Loeys–Dietz syndrome and/or familial thoracic aortic aneurysm and dissection were also found to have COL3A1 variants. Twenty cases (57.1%) had missense variants leading to glycine (Gly) substitutions in the triple helical domain, one (2.9%) had a missense variant leading to non-Gly substitution in this domain, eight (22.9%) had splice site alterations, three (8.6%) had nonsense variants, two (5.7%) had in-frame deletions, and one (2.9%) had a multi-exon deletion, including two deceased patients analyzed with formalin-fixed and paraffin-embedded samples. This is a clinically useful system to detect a wide spectrum of variants from various types of samples.  相似文献   
79.
Overexpression of P-glycoprotein (Pgp) in tumors is one of the major mechanisms which mediates the multidrug resistance (MDR) phenotype. To evaluate the prognostic significance of Pgp in breast cancer, Pgp expression was examined in paraffin-embedded tissue sections of 94 breast cancer specimens by immunohistochemistry. Tissue specimens were obtained by mastectomy without preoperative chemotherapy. UIC2 monoclonal antibody which recognizes an extracellular epitope of human Pgp was employed. Of the 94 breast cancer specimens, 35 (37.2%) were positive for Pgp expression. Pgp expression had no correlation with menopausal or hormone receptor status, axillary lymph node involvement or tumor size. However, a significant correlation was observed between Pgp expression and disease relapse (p = 0.0322). Pgp-positive patients showed a significantly shorter disease-free survival period than Pgp-negative patients by the Kaplan-Meier method (p = 0.0433). These results suggest that immunohistochemical detection of Pgp in breast cancer tissue may have prognostic value after radical operation.  相似文献   
80.
BACKGROUND: Recombinant human erythropoietin (rHuEPO) is primarily used for patients with anemia associated with end-stage renal disease. We evaluated the efficacy of EPO gene therapy using adenovirus vector for chronic renal failure mice expressing severe renal anemia. METHODS: Recombinant HuEPO gene transfer to mesothelial cells was performed in vitro and in vivo. Recombinant replication-deficient adenoviruses containing rHuEPO cDNA (AdCMVEPO), E. coli lacZ gene (AdCMVlacZ), or an nonexogenous gene (AdNull as control vector) driven by the cytomegalovirus promotor/enhancer were constructed. The oligosaccharides associated with the rHuEPO from AdCMVEPO-treated mesothelial cells were analyzed. For in vivo study, the DBA/2FG-pcy mouse, a model for human autosomal recessive polycystic kidney disease resulting in chronic renal failure with progressive anemia, was used. RESULTS: The sialylated oligosaccharides associated with the rHuEPO produced in AdCMVEPO-treated mesothelial cells occupied 78 +/- 0.7% of the total oligosaccharide pool. A single intraperitoneal administration of AdCMVEPO induced rHuEPO synthesis in the peritoneal cells and a marked increase in erythrocyte production. The maximal increase in hematocrit (43 +/- 4%) was observed on day 28, and it remained elevated for 40 days. CONCLUSION: These results indicate that intraperitoneal administration of AdCMVEPO improves renal anemia in mice with chronic renal failure and that the mesothelial cell is an appropriate target cell for gene transfer.  相似文献   
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