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41.
A unique characteristic of the localized inflammatory tissue in the periodontium (e.g., adult periodontitis [AP]) is the accumulation of IgG (IgG1 > IgG2 > IgG3 > or = IgG4) followed by IgA plasma cells (IgA1 > IgA2). However, the exact molecular mechanisms contributing to these elevated B-cell responses at the local disease site are still unknown. Thus, this study has examined the production of cytokines of importance in B-cell responses, e.g., interleukin (IL)-2, IL-4, IL-5, and IL-6 by gingival mononuclear cells (GMC) isolated from patients in severe stages of AP. These cytokines were assessed at the protein and messenger (m)RNA levels to understand their importance for the observed increased B-cell responses present in these tissues. Among the four cytokines tested by respective cytokine-specific, polymerase chain reaction and dot-blot hybridization, high levels of IL-5- and IL-6-specific mRNA were noted in GMC freshly isolated from AP patients. On the other hand, specific message for IL-2 and IL-4 were not present. Further, the analysis of culture supernatants of GMC also revealed that cells from AP patients spontaneously produced IL-5 and IL-6 but not IL-2 and IL-4. In contrast, when peripheral blood mononuclear cells isolated from the same patients were examined for these cytokines, no detectable levels of mRNA or secreted cytokines were noted. These results showed that GMC from localized inflammatory tissues in severe stages of AP possess a distinct cytokine profile represented by high levels of IL-5 and IL-6 mRNA expression and protein synthesis, whereas IL-2 and IL-4 were not detected. Further, this study supports the concept that AP is a localized inflammatory disease, because GMC from the inflamed tissue actively produce IL-5 and IL-6, whereas peripheral blood mononuclear cells from the same patients do not.  相似文献   
42.
Fibronectin and C1q frequently co-precipitated in cryoglobulins from patients with SLE. As a portion of the C1q molecule is similar to collagen to which fibronectin has a high affinity, we studied whether fibronectin specifically bound to C1q. Fibronectin was found to bind to both native and heat-inactivated C1q. The binding was enhanced by Ca++ and low ionic strength. We have also demonstrated that fibronectin is capable of binding to C1q fixed to immune complexes. The interaction between fibronectin and C1q may play a role in cryoglobulin formation and in clearance of immune complexes by reticuloendothelial system.  相似文献   
43.
We report on an 8-year-old Japanese boy with Setleis syndrome. The patient had a very characteristic “coarse” facial appearance, bitemporal “forceps marks,” skin aplasia, sparse hair, and skin hypo- and hy-perpigmentation. He also had previously undescribed manifestations, including an aberrant hair pattern of the forehead, linear skin lesions on the forehead, short palpebral fissures, a small skin tag on the right cheek, cone-shaped teeth, and pectus carinatum. Dermatoglyphic studies documented aberrant distal palmar creases (simian crease variant), 8 arches, and reduced total finger ridge count. When serial photographs were reviewed, his facial characteristics became more obvious with increasing age. © 1995 Wiley-Liss, Inc.  相似文献   
44.
Liposomes could bind and fuse efficiently to human erythrocytes in the presence of HVJ when they contained gangliosides isolated from human erythrocytes. Sialosylparagloboside, which has a terminal sequence of NeuAcα2?3Ga1β1?4GlcNac, has a much higher receptor activity to the virus than GD1a, GD1b, GT1b, and GT1a, all of which contain the terminal sequence of NeuAcα2?3Galβ1?3GalNAc or NeuAcα2?8NeuAcα2?3Galβ1?3GalNAc. The activity of sialosylparagloboside is comparable to that of glycophorin, a major sialoglycoprotein of human erythrocytes, when compared on the basis of the required amount (as sialic acid) of compounds. The high affinity of sialosylparagloboside to the viral HANA protein is also suggested by the finding that it showed high inhibitory activity against HVJ-mediated binding of glycophorin liposomes to erythrocytes. Sialosylparagloboside was also highly susceptible to the viral sialidase, the other biological function of HANA protein.  相似文献   
45.
ABSTRACT: Human leukocyte antigen (HLA) genes are candidates for susceptibility genes in insulin-dependent diabetes mellitus (IDDM). Recently, the association of DR and DQ with IDDM has been reported, but the role of HLA-DP genes remains uncertain. To address the question, we analyzed the DPB1 gene of 20 Japanese IDDM patients and 30 control subjects using a combination of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis (PCR-RFLP method). DPB1*0501 was the most frequent allele both in Japanese patients and control subjects. There was no appreciable association between IDDM and the DPB1 allele in Japanese. The absence of association between IDDM and DP, in spite of the known association between this disease and both DR and DQ, suggests that the HLA locus (loci) telomeric to DP encodes susceptibility to IDDM.  相似文献   
46.
This is a case report of a malignant mesenchymoma of the esophagus in a 50?year-old Japanese man. The tumor was a sessile polypoid mass showing a downward invasion limited to the submucosa of the esophagus. Histologically, the lesion contained rhabdomyosarcomatous and osteosarcomatous areas, in addition to an ill-defined fibrosarcomatous element. In contrast with reports of carcinosarcoma up to the present, this tumor lacked any invasive lesion of an epithelial malignancy. The morphogenesis of these tumor groups was discussed from a hamartoblastomatous standpoint. Acta pathol. jpn. 34: 925~933, 1984.  相似文献   
47.
Summary.  A virus, named Oya virus, was isolated in Vero cell cultures from the lungs of a pig suspected of Nipah virus infection. The virus was revealed as a spherical enveloped RNA virus with a diameter of 79 nm. For identification of Oya virus, RT-PCR was performed. A common primer set for S-RNA of the Simbu serogroup of the genus Bunyavirus was able to amplify a cDNA from Oya virus RNA. The sequence data of the product revealed that the partial gene of Oya virus S-RNA segment had 65–70% homology with published cDNA sequences of Simbu serogroup viruses. The phylogenetic analysis of the data showed that the Oya virus is grouped in Simbu serogroup, but is genetically distinct from the serogroup viruses that have been analyzed molecularly. Serological surveys revealed that the virus distributed widely and densely in Malaysia. Received January 5, 2002; accepted April 16, 2002 Published online July 19, 2002  相似文献   
48.
When uremic blood flows through dialyzers during hemodialysis, dialysis membrane surfaces are exposed to shear stress and internal filtration, which may affect the surface characteristics of the dialysis membranes. In the present study, we evaluated changes in the characteristics of membrane surfaces caused by shear stress and internal filtration using blood substitutes: water purified by reverse osmosis and 6.7 wt% dextran70 solution. We focused on the levels of a hydrophilic modifier, polyvinylpyrrolidone (PVP), on the membrane surface measured by attenuated total reflectance Fourier transform infrared spectroscopy. Experiments involving 4 h dialysis, 0-144 h shear-stress loading, and 4 h dead-end filtration were performed using polyester-polymer alloy (PEPA) and polysulfone (PS) membranes. After the dialysis experiments with accompanying internal filtration, average PVP retention on the PEPA membrane surface was 93.7% in all areas, whereas that on the PS membrane surface was 98.9% in all areas. After the shear-stress loading experiments, PVP retention on the PEPA membrane surface decreased as shear-stress loading time and the magnitude of shear stress increased. However, with the PS membrane, PVP retention scarcely changed. After the dead-end filtration experiments, PVP retention decreased in all areas for both PEPA and PS membranes, but PVP retention on the PEPA membrane surface was lower than that on the PS membrane surface. PVP on the PEPA membrane surface was eluted by both shear stress and internal filtration, while that on the PS membrane surface was eluted only by internal filtration.  相似文献   
49.
cDNAs encoding human parainfluenza virus type 4B (hPIV-4B) hemagglutinin neuraminidase (HN) protein were cloned and the nucleotide sequences were determined. A high degree of identity (81.4%) was observed between the nucleotide sequences of hPIV-4A and -4B HN proteins, and an 87.3% identity was found between the deduced amino acid sequences. This degree of identity is considered to be greater than immunological similarity between hPIV-4A and -4B HN proteins determined using monoclonal antibodies. To elucidate the causes of the antigenic difference between HN proteins of hPIV-4A and -4B, we constructed three cDNAs of hPIV-4B HN whose potential N-glycosylation sites were partially or completely the same as in hPIV-4A HN cDNA. We compared the antigenicity of the expressed wild-type and mutant proteins, and found that the antigenicities of the mutant hPIV-4B HN proteins were more similar to the hPIV-4A HN protein than to the non-mutant hPIV-4B HN protein. This study indicated that the antigenic diversity between hPIV-4A and -4B was partly caused by deletion or creation of glycosylation sites, showing that the point mutations resulting in deletion or creation of glycosylation sites is one of the initial steps leading to the division of virus into subtypes. Received: 21 January 2000  相似文献   
50.
Japanese encephalitis virus-specific IgM is a reliable indicator for serodiagnosis of Japanese encephalitis. A particle agglutination (PA) assay system was developed to detect anti-Japanese encephalitis virus IgM in human serum samples. The newly developed PA assay consisted of hydroxyapatite-coated nylon beads and V-bottom 96-well microplates. Hydroxyapatite-coated nylon beads were coated with Japanese encephalitis virus antigens. Japanese encephalitis virus antigen-coated, hydroxyapatite-coated nylon beads agglutinated in the IgM-captured wells when anti-Japanese encephalitis virus IgM-positive serum samples were used. A button pattern was formed at the bottom of the wells when anti-Japanese encephalitis virus IgM-negative serum samples were used. Thirty anti-Japanese encephalitis virus IgM-positive serum samples from Japanese encephalitis-confirmed cases were tested by the PA assay. All these serum samples were determined to be Japanese encephalitis virus IgM-positive. IgM titers determined by the PA assay corresponded to those determined by enzyme-linked immunosorbent assay. The titers were consistent in two independent PA assays. These results indicate that the newly developed PA assay is a reliable method for detecting anti-Japanese encephalitis virus IgM in human serum samples and that this assay will be a suitable diagnostic system especially in rural areas of Asia.  相似文献   
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