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41.
42.
Summary A cDNA clone representing the VP4-encoding gene of human rotavirus strain 69M(VP7 serotype 8) was constructed and inserted into a baculovirus expression vector. Baculovirus recombinants that expressed the 69 M VP4 protein inSpodoptera frugiperda (Sf9) cells were screened by immunofluorescence with hyperimmune antiserum to the 69M strain and purified by terminal dilution. The expressed VP4 was detected by Coomassie blue staining of PAGE-separated proteins. The antigenic relationships between the VP4 of the 69M strain and those of various human and other animal rotavirus strains representing ten established VP4 serotypes were examined by plaque reduction neutralization. Hyperimmune antiserum produced in guinea pigs following immunization with a lysate of Sf9 cells infected with a 69M gene 4-baculovirus recombinant neutralized the infectivity of the homologous human rotavirus 69M strain as well as heterologous equine rotavirus H-2 strain to a high titer. The anti-69M VP4 hyperimmune antiserum did not neutralize significantly other rotavirus strains of human, simian, porcine, bovine, or murine origin. It thus appears that the human rotavirus 69M strain has a distinct VP4 serotype (designated as P serotype 4) which is closely related antigenically to equine rotavirus H-2 VP4. 相似文献
43.
N. Kariya K. Hayashi H. Hoshino Y. Tanaka T. R. Koirala N. Ohara K. Miyamoto T. Akagi 《Archives of virology》1996,141(3-4):471-480
Summary Rabbit immune sera raised against synthetic peptides of the HTLV-II envelope gp46 region were examined for HTLV-II neutralization ability by HTLV-vesicular stomatitis virus (VSV) pseudotype assay and syncytium inhibition assay. HTLV-II neutralization activity was detected in the sera against HTLV-II Env gp46, 80–103 but not in those to HTLV-II Env gp46, 171–196. Three rabbits immunized with the synthetic peptide of HTLV-II Env gp46, 80–103 and three non-immunized rabbits were challenged with intravenous inoculation of an HTLV-II-producing human cell line (MOT, 1×107 cells). The non-immunized rabbits showed seroconversion for HTLV-II after 2 weeks and maintained persistent infection but the immunized rabbits were protected from HTLV-II infection. Nested or repeated polymerase chain reaction revealed the presence of HTLV-II provirus sequences in the non-immunized rabbits but not in the immunized rabbits. These results suggest that peptide vaccination with a synthetic peptide corresponding to the HTLV-II neutralization region is useful for preventing HTLV-II infection. 相似文献
44.
Immunohistochemical study of neuron specific enolase and S-100 protein in Hirschsprung's disease 总被引:3,自引:0,他引:3
Tomoaki Taguchi Kenzo Tanaka Keiichi Ikeda 《Virchows Archiv : an international journal of pathology》1985,405(4):399-409
Summary The distribution of whole differentiated neurons in the intestines from 15 children with Hirschsprung's disease was investigated using neuron specific enolase (NSE) and the perineuronal elements were studied using S-100 protein immunostaining.In aganglionic segments, NSE immunoreactive ganglion cells and S-100 positive satellite cells were absent, but the hypertrophic nerve trunks did show a markedly positive NSE and S-100 immunoreactivity.Two different forms of aganglionic segment were present. One was the middle aganglionic segment of long segment aganglionosis which was almost completely dennervated. In the other type, there were several NSE positive nerve fibers in the muscularis propria of both the aganglionic segment of short segment aganglionosis and the distal aganglionic segment of long segment aganglionosis. These latter two aganglionic segments seemed to be innervated by extrinsic nerves. 相似文献
45.
Konno A Hoshino Y Terashima S Motoki R Kawaguchi T 《Clinical & experimental metastasis》2002,19(1):61-70
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer. 相似文献
46.
Chemical composition and immunological characterization of polysaccharide antigen from Eubacterium saburreum T18.
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Two types of polysaccharide were obtained from the oral microorganism Eubacterium saburreum T18 by formamide extraction and subsequent gel filtration and ion-exchange chromatography. One polysaccharide, which was composed of D-glycero-D-galacto-heptose, had antigenic activity in an immunoprecipitation reaction with rabbit anti-T18 serum due to immunoglobulin M antibodies. The second polysaccharide was composed of D-glycero-D-manno-heptose and L-rhamnose, but it did not have immunoprecipitation activity. These polysaccharide antigens were not alkali labile and differed from E. saburreum L44 and T27 antigens, which were composed of D-glycero-D-galacto-heptose. 相似文献
47.
48.
Mitani H Ishiyama Y Hoshino H 《Rinsho byori. The Japanese journal of clinical pathology》2000,48(9):880-883
The aims of this paper are to make clear the characteristics of sympathetic skin response(SSR) wave. The records of SSR wave were obtained using a DC servo-amplifier with the frequency response of DC to 30 Hz and drift level of 10 microV/10 min. The SSR from the palm of 10 normal control subjects(6 males and 4 females, age range 21-25 yrs) were elicited by electrical stimulation of the median nerve at upper arm. The results that the peak latency and the duration of SSR were approximately 6.32 +/- 2.5 s and 47.5 +/- 7.5 s respectively were obtained experimentally with the amplifier, though the results of AC recordings with time constant of 0.3 s were about 1.0 s and 2.0 s respectively. It can be considered that exact peak latency and duration of SSR are much longer than those data of previous studies. These findings suggest that electric stimulation should be applied at longer intervals than 60 s for rejection of the remaining potential level of SSR and the habituation. 相似文献
49.
Summary Coronavirus-like particles, morphologically indistinguishable from coronavirus-like particles seen in human, canine, and simian feces, were detected by electron microscopy in the feces from both feline infectious peritonitis antibody-positive and antibody-negative cats.With 2 FiguresSupported by a grant from the Robert H. Winn Foundation of the Cat Fancier's Association, Inc., a grant from Pitman-Moore, Inc., Washington Crossing, N.J., and private contributions to the Cornell Feline Research Laboratory. 相似文献
50.
T Hoshino S Yamashita N Sakai Y Matsuzawa S Tarui K Kumasaka 《Rinsho byori. The Japanese journal of clinical pathology》1989,37(7):835-839
Lipoprotein metabolism was analyzed in a patient with marked hyper-HDL-cholesterolemia. A 50 year old male with no symptom of ischemic heart disease or xanthoma had a serum cholesterol level between 293 and 410 mg/dl, and a markedly elevated, HDL-cholesterol level (160-190 mg/dl). The cholesterol content of ultracentrifugally separated HDL2 was exclusively increased, while it was normal in the HDL3 fraction. Analytical ultracentrifugation and HPLC revealed that HDL particles became remarkably larger than the control and, on the contrary, LDL particles became smaller. LPL and LCAT activities were higher in this case, but H-TGL activity was normal. Agarose gel electrophoresis of lipoproteins showed an abnormal broad band which was located between alpha and pre beta band. Serum levels of apolipoprotein A-I, A-II, C-II, C-III and E were higher, while apolipoprotein B level was slightly lower than the control. Cholesteryl ester transfer protein (CETP) activity was demonstrated to be completely deficient in this case, as determined in 10 microliters serum using [3H] CE-labeled HDL3 as donor and VLDL + LDL fraction as acceptor. Since CETP was considered to catalyze the cholesteryl ester transport from HDL to VLDL and LDL, the deficiency of this activity might be the cause of the marked hyper-HDL-cholesterolemia in this patient. 相似文献