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91.
Maya Kummrow Marina L. Meli Michael Haessig Enikoe Goenczi Amy Poland Niels C. Pedersen Regina Hofmann-Lehmann Hans Lutz 《Clinical and Vaccine Immunology : CVI》2005,12(10):1209-1215
To determine the prevalence of antibodies to feline coronavirus (FCoV) serotypes 1 and 2 in Switzerland and their association with different disease manifestations, a serological study based on immunofluorescence tests was conducted with Swiss field cats using transmissible gastroenteritis virus (TGEV), FCoV type 1 and FCoV type 2 as antigens. A total of 639 serum samples collected in the context of different studies from naturally infected cats were tested. The current study revealed that, with an apparent prevalence of 83%, FCoV serotype 1 is the most prevalent serotype in Switzerland. FCoV type 1 viruses induced higher antibody titers than FCoV type 2, and were more frequently associated with clinical signs and/or feline infectious peritonitis. The antibody development in seven cats experimentally infected with FCoV type 1 revealed that, with progressing duration of infection, antibodies to FCoV type 1 significantly increased over those to FCoV type 2. There was a significant relationship between antibody titers against TGEV, FCoV 1, and FCoV 2 and TGEV antigen detected the highest proportion of seropositive cats. We conclude that a vaccine against FCoV should be based on FCoV type 1-related antigens and that for serodiagnosis of FCoV infection TGEV should be used to attain the highest diagnostic efficiency. When serology is used in addition to clinical signs, hematology, and clinical chemistry results as an aid to diagnose clinical FIP, TGEV shows a diagnostic efficiency equal to that of a FCoV antigen. 相似文献
92.
Investigation of the complexity of barley stripe mosaic virus RNAs with recombinant dna clones 总被引:2,自引:0,他引:2
RNA isolated from the Type, ND18, and Norwich strains of barley stripe mosaic virus (BSMV) was electrophoresed in agarose gels, transferred to nitrocellulose, and hybridized with BSMV-specific complementary DNA (cDNA) or recombinant DNA clones derived from ND18 RNA. Genomic RNA components 1 (Mr = 1.43 x 10(6)) and 2 (Mr = 1.24 x 10(6)) were resolved in all three strains, but RNA 3 (Mr = 1.1 x 10(6)) was seen only in the ND18 and Norwich strains. A low-molecular-weight RNA (Mr = 0.27 x 10(6)), thought to be a subgenomic (SG) RNA, was also detected in RNA preparations from all three strains by staining with toluidine blue or ethidium bromide and by hybridizing with cDNA or selected recombinant DNA probes. Three classes of recombinant DNA clones, designated pBSM1, pBSM2, and pBSM3, were identified by hybridization of nick-translated recombinant DNA to electrophoretically separated viral RNAs. Clones in the pBSM1 class hybridized only to RNA 1 of all three strains and class pBSM2 clones hybridized only to RNA 2 of all three strains. Class pBSM3 clones hybridized to RNA 3 of the ND18 and Norwich strains and to RNA 2 of the Type strain, but not to RNA 2 of ND18 or Norwich. Based on the sizes of the BSMV-specified inserts in clones designated pBSM1a, pBSM2a, and pBSM3a, we estimate that a minimum of 44, 63, and 63% of the nucleotide sequences of ND18 and Norwich RNAs 1, 2, and 3, respectively, are unique. Furthermore, because the combined size of the inserts in pBSM2a and pBSM3a is approximately 15% greater than the estimated size of RNA 2, it is probable that the second RNA component of the Type strain actually consists of two RNA species which are similar in size but have different sequences. The SG RNA component is viral specific and contains sequences common to clones derived from RNA 3. 相似文献
93.
94.
Immunological Studies on the Envelope Component of Venezuelan Equine Encephalomyelitis Virus 总被引:5,自引:1,他引:5
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Treatment of purified Venezuelan equine encephalomyelitis virus with the nonionic detergent Triton X-100 permitted spearation of the envelope from the core component. The isolated envelope was a noninfectious immunogen which reacted in hemagglutination, hemagglutination inhibition, complement fixation, and neutralization serological reactions. 相似文献
95.
Anne Hansen Ree Kristin Bjørnland Nils Brünner Harald Thidemann Johansen Kjetil Boye Pedersen Ansgar O. Aasen Øystein Fodstad 《Clinical & experimental metastasis》1998,16(3):205-215
Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (~10- fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, am ongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were ~10-fold and ~15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immuno-reactive PAI-1 was considerably elevated (. 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only ~2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (~10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associ-ated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer. © Rapid Science 1998 相似文献
96.
Lindegaard B Keller P Bruunsgaard H Gerstoft J Pedersen BK 《Clinical and experimental immunology》2004,135(2):273-279
This study tested the hypothesis that in patients with HIV-associated lipodystrophy, adiponectin levels were related to insulin resistance, TNF-alpha and IL-6 and treatment with nucleoside analogues. HIV seropositive men undergoing highly active antiretroviral treatment were enrolled into three predetermined clinical groups: lipodystrophy with central fat accumulation (n = 12); lipodystrophy without central fat accumulation (n = 15); no lipodystrophy (n = 15). HIV-negative healthy men served as controls (n = 12). Both lipodystrophic groups had a low percentage of limb fat compared to the two control groups. Patients with lipodystrophy with fat accumulation had increased truncal fat compared with controls. Levels of adiponectin did not correlate with either TNF-alpha or IL-6. Low levels of adiponectin were found in both lipodystrophic groups and were associated with current or previous treatment with stavudine. Furthermore, the adiponectin level correlated with the percentage of limb fat. Patients with lipodystrophy with fat accumulation were more insulin resistant, measured by HOMA-IR, compared with controls. However, HOMA-IR did no correlate to adiponectin or other cytokines. In conclusion, the finding of no difference between the two lipodystrophic groups with regard to adiponectin, indicates that low levels of adiponectin reflects fat atrophy, whereas the insulin resistance was best explained by increased truncal fat mass. 相似文献
97.
BACKGROUND: Measurement of short-term lower-leg growth rate in children by means of knemometry has become established as an integral part of the available measures of systemic activity of topical steroids in children. OBJECTIVE: We sought to determine the effects of clinically effective doses of the novel inhaled corticosteroid ciclesonide on lower-leg growth rate and hypothalamic-pituitary-adrenal axis function in children with asthma. METHODS: In a double-blind, placebo-controlled, 4-period crossover study, 24 children aged 6 to 12 years sequentially received ciclesonide (40, 80, and 160 microg) in randomized order once daily in the evening. Each 2-week treatment period was followed by a 2-week washout period. Knemometry was performed at the beginning and end of each treatment period. Cortisol levels in 12-hour overnight urine were measured at the end of each treatment period. RESULTS: No statistically significant differences were seen in lower-leg growth rates between any of the ciclesonide treatments and placebo. Lower-leg growth rates were 0.412 mm/wk for placebo, 0.425 mm/wk for 40 microg of ciclesonide, 0.397 mm/wk for 80 microg of ciclesonide, and 0.370 mm/wk for 160 microg of ciclesonide. There was no statistically significant dose-response effect. Likewise, no statistically significant differences or dose-response effects were found for urinary cortisol adjusted for creatinine. CONCLUSION: Short-term lower-leg growth rate and hypothalamic-pituitary-adrenal axis function are not affected by treatment with ciclesonide in doses intended for clinical use in children. 相似文献
98.
Enzyme-linked immunosorbent assay for detection of immunoglobulin M antibody against the Reiter treponeme flagellum in syphilis 总被引:8,自引:5,他引:8
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An enzyme-linked immunosorbent assay (ELISA) for detection of immunoglobulin M (IgM) antibodies against the periplasmatic flagellum of the Reiter treponeme is described. IgM in the test samples was bound to anti-IgM-coated microtest plates, and flagellum-specific IgM antibody was subsequently detected by incubation with a purified flagellum preparation and monospecific anti-flagellum conjugate. Rheumatoid factor, antinuclear antibodies, or flagellum-specific IgG did not interfere. The specificity of the ELISA for IgM antibodies was 99.5% for sera from 200 blood donors and 98.6% for 147 patient sera that gave false-positive reactions in other syphilis serological tests. The sensitivity was 88.5% for sera from 87 patients with first-time primary syphilis, 93.5% for sera from 62 patients with first-time secondary syphilis, 21.4% for sera from 42 patients who were reinfected, and 0% for sera from 13 patients with late syphilis. Of the sera from 153 patients with treated syphilis, 7.2% had IgM antibodies, and sera from patients with primary or secondary syphilis generally had no IgM antibodies 6 months after treatment. The finding of IgM antibodies indicates that patients should receive antisyphilis treatment if they have not been treated recently, but a negative result does not exclude the possibility of active syphilis. The method may prove useful for the diagnosis of congenital syphilis in newborns. 相似文献
99.
Improved method for production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine. 总被引:1,自引:0,他引:1
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F E Cole Jr C E Pedersen Jr D M Robinson G A Eddy 《Journal of clinical microbiology》1976,3(4):460-462
Primary chicken embryo cell cultures were evaluated a s an alternate cell system for the production of attenuated Venezuelan equine encephalomyelitis (TC-83 strain) vaccine. The TC-83 strain virus was shown to remain stable during 10 serial passages in chicken embryo cell culture with regard to plaque size and morphology, virus yield, potency, and virulence for mice and hamsters. 相似文献
100.