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31.
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time.  相似文献   
32.
We developed a system for discriminating HLA-B40, B18, B27, and B37 alleles using a two-step PCR method followed by SSCP analysis. Fragments (0.8 kb) including exon 2, intron 2, and exon 3 were amplified in the first PCR. We used two sets of primers, one specific for HLA-B60-related alleles and the other specific for HLA-B6l-related, B18, B27, and B37 alleles. No amplifications of other class I genes or pseudogenes were observed. In the second PCR, exon 2 and exon 3 were amplified separately, using diluents of the first PCR products as templates. HLA-B6l-related, B18, B27, B37, and B60-related alleles were clearly discriminated in the SSCP analysis of the second PCR products. In a population study in which B6l alleles were analyzed, B*4003 was detected in two Japanese individuals in addition to two B6l alleles previously reported to occur in Japanese, B*4002 and B*4006. The relative frequencies of B*4002, B*4006, and B*4003 in Japanese were 58, 35, and 6%, respectively. The individuals having B*4003 are the first non-South Americans in whom this allele has been detected. The SSCP banding patterns of 18 HLA-B60-positive Japanese population samples were identical to those of a B*40012 sample for both exon 2 and exon 3. We also demonstrated that the B37 allele occurring in some Japanese is B*3701.  相似文献   
33.
A case with lymphadenopathy of the left side of the neck in a 38-year-old male is described. He had a history of several relapses of about 10 years duration. Swollen lymph nodes were histologically similar to those of the hyaline-vascular type of Castleman's disease, but contained clear-cut lymph sinus and a sheet-like proliferation of plasma cells. Lymph follicles showed proliferation and atrophic germinal centers, in which cellular hypertrophy in the wall of ramifying small blood vessels, called angiosclerosis, was frequently encountered. During its progress, the patient developed plasmacytoma of the lymph nodes with varied clinical manifestations such as polyneuropathy, disturbance of gait, unusual perspiration, hirsuitism, gynecomastia, bilateral papilledema, and albumino-cytologic dissociation in cerebrospinal fluid.  相似文献   
34.
The 6-amino-6-deoxy-N-acetylmuramyldipeptides and their 6-acylamino derivatives were shown to be active as adjuvants on the induction of delayed-type hypersensitivity to azobenzenearsonate-N-acetyl-l-tyrosine in guinea pigs. However, 6-acylamino-6-deoxy-N-(acyl)muramyldipeptides were inactive as adjuvants.  相似文献   
35.
36.
The effect of polyanions on the formation of mixed dimers of methylene blue ( 1 ) and trypaflavine ( 2 ), methylene blue ( 1 ) and phenosafranine ( 3 ), and methylene blue ( 1 ) and pyronine G ( 4 ) was investigated spectrophotometrically. The following polyanions were used: poly(potassium styrenesulfonate) (PSS), poly(potassium vinyl sulfate) (PVS), and poly(sodium acrylate) (PAA). On addition of polyanions, the formation of mixed dimers was enhanced largely. Thermodynamic parameters inferred that the enhancement of the formation of mixed dimers in the presence of polyanions resulted from an entropic factor.  相似文献   
37.
Three cases of pancreatoblastoma in children were examined immunohis-tochemically and the results were compared with those of pancreatic duct carcinoma in adults. The pancreatoblastoma demonstrated positive reactions to α-fetoprotein (AFP) (67%: 2/3), α-1-antitrypsin (AAT) (100%: 3/3), carcinoembryonic antigen (CEA) (67% : 2/3) and keratin (33% : 1/3), although CEA was only weakly positive in both cases. On the other hand, adult pancreatic duct carcinoma showed positive reactions as follows; AFP: 3% (1/29), AAT: 21% (6/29), CEA: 97% (28/29) and keratin: 93% (27/29). Also, endocrine substances including insulin, glucagon and somatostatin were all negative in the pancreatoblastomas. Two cases of pancreatoblastoma which were immunohistochemically positive for AFP also showed elevation of the serum AFP level clinically. The different expressive pattern of oncofetal antigens in pancreatoblastoma as compared with pancreatic duct carcinoma in adults may provide further supporting evidence for the embryonic nature of pancreatoblastoma, and suggests that such a pattern might be used as a tumor marker for pancreatoblastoma. ACTA PATHOL. JPN. 37 : 1581-1590, 1987.  相似文献   
38.
Heme oxygenase (HO), the heme-degrading enzyme, plays an important role in heme catabolism. Among three isozymes, HO-1 is an inducible form expressed mainly in macrophages. In rat ontogeny, HO-1 immunoreactivity was detected in mononuclear cells in the yolk sac at 10 days of gestation. HO-1-expressing cells were then detected in the fetal liver and their numbers increased during the gestational period. The numbers of HO-1-positive cells and HO-1 mRNA levels in the liver peaked at 18 days of gestation. Most of the macrophages expressed both HO-1 and a macrophage scavenger receptor. Macrophages in the fetal liver showed marked hemophagocytosis. Macrophages in the lung, spleen, bone marrow, and other tissues also expressed HO-1. HO-1 immunoreactivity was also observed in syncytial cells of the chorionic villi, the endodermal layer of the yolk sac, and renal tubules of the fetus. Intestinal mucosal epithelial cells expressed HO-1 after birth. These findings imply that HO-1 is crucial for macrophages in heme catabolism from an early stage of ontogeny. HO-1 expression in non-macrophagic cells may be required for other purposes such as protection from oxidative stress and various stimuli.  相似文献   
39.
40.
Dendritic cell-like cells (Mo-DCs) generated from peripheral blood monocytes with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been used as tools to treat cancer patients (DC-vaccines). Because Mo-DCs have multiple antigen presentation-related functions, including phagocytosis, migration, cytokine production, and T cell stimulation, establishment of a method for simultaneously evaluating the various functions of Mo-DCs is important. We developed a new in vitro three-dimensional two-layer collagen matrix culture model that consists of a collagen gel containing Mo-DCs as the lower layer and a collagen gel containing necrotic GCTM-1 tumor cells and/or T cells as the upper layer. We used this system to observe simultaneously multiple functions of Mo-DCs by phase-contrast or fluorescence microscopy and to assess IL-12 secretion during more than 2 weeks of culture. We also observed interactions between Mo-DCs and necrotic GCTM-1 or T cells on an individual cell basis by time-lapse videomicroscopy. In addition, we collected Mo-DCs from the collagen gels by collagenase treatment and analyzed the expression of antigen presentation-related molecules such as HLA-DR, CD80, CD83, and CD86 on Mo-DCs. This model may be a useful tool for evaluation of the various functions of Mo-DCs used as DC vaccines and for studies of the complex behaviors of Mo-DCs in vivo.  相似文献   
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