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61.
62.
We compare the results of direct immunofluorescence (IF) with cytology (Papanicolaou's stains) for diagnosis of herpes simplex infection. Thirty smears were examined. Yellow-green fluorescence was seen in 17 smears. Only eight of these smears had diagnostic cytology, and nine of the smears with positive fluorescence had none (four) to minimal (five) cytologic changes, suggesting that direct IF is a much more sensitive method for diagnosis of herpes simplex infection in cytologic smears. 相似文献
63.
Masciotra S Rudolph DL van der Groen G Yang C Lal RB 《Clinical and diagnostic laboratory immunology》2000,7(4):706-709
Cross-species transmission has been shown to play an important role in the emergence of human retroviruses. We developed a generic enzyme immunoassay using synthetic peptides from gp41 and C2V3 consensus sequences (human immunodeficiency virus [HIV] type 1 [HIV-1] groups M, O, and N and the homologous region of simian immunodeficiency virus [SIV] strains from chimpanzees [SIVcpz], SIVcpzGAB1 and SIVcpzANT) to detect divergent HIV and SIV. A cocktail of peptides from gp41 and C2V3 (M-O) detected all HIV-1 group M and O sera and showed cross-reactivity with SIVcpz sera. Further, a mixture of C2V3 peptides (GAB1-ANT) failed to detect HIV-1 infections but reacted with all SIVcpz sera, allowing discrimination of SIVcpz from HIV-1 infections. Since most SIVcpz sera cross-reacted with HIV-1 peptides, we next evaluated SIVcpz serum reactivity with rapid tests for HIV-1/2. SIVcpzANT and SIVcpzUS sera reacted with the Sero-strip and Multispot assays. Both tests are sensitive in detecting group M (97 100%, respectively), although Multispot has lower sensitivity for group O detection (67%) than does Sero-strip (100%). The limited volume and time required to perform these assays make them a generic tool for field screening. The env peptide-based assay and rapid tests should allow for the identification of emerging variants of HIV and SIV. 相似文献
64.
Immunologic cross-reactivity between structural proteins of human T-cell lymphotropic virus type I and the blood stage of Plasmodium falciparum. 下载免费PDF全文
R B Lal D Rudolph M P Alpers A J Sulzer Y P Shi A A Lal 《Clinical and Vaccine Immunology : CVI》1994,1(1):5-10
To determine the serologic cross-reactivity between human T-cell lymphotropic virus type I (HTLV-I) and parasite antigens, we measured antibody responses against HTLV-I, Plasmodium falciparum, Plasmodium vivax, and Brugia malayi in serum specimens obtained from regions where malaria (n = 482) and filariasis (n = 101) are endemic. Analysis of immune reactivity to HTLV-I antigens showed that specimens from regions where malaria is endemic had significantly higher rates of enzyme immunoassay (EIA) reactivity (76 of 482 [15.8%] than those from regions where filariasis is endemic (0 of 101 [0%]). Western blot (immunoblot) analysis of the HTLV-I EIA-reactive specimens demonstrated predominant Gag reactivity (HTLV-Iind). Only two specimens each from Indonesia and Brazil and four specimens from Papua New Guinea had Env reactivity by radioimmunoprecipitation analysis. Furthermore, a positive correlation between HTLV-EIA and titers of antibody to the blood stage of P. falciparum (rs = 0.24, P < 0.005) was discerned; no correlation was observed between antibodies to the blood stage or the circumsporozoite protein of P. vivax and the circumsporozoite protein of P. falciparum. In addition, P. falciparum-infected erythrocyte lysate specifically abrogated binding of Gag-specific antibodies in HTLV-Iind specimens from regions where malaria is endemic without affecting binding in HTLV-I-seropositive specimens, suggesting that the immunologic cross-reactivity between HTLV Gag proteins and malaria parasites is restricted to the blood-stage antigens of plasmodia in specimens from regions where malaria is endemic. However, HTLV-seroindeterminate specimens from the United States did not demonstrate serologic cross-reactivity, suggesting that antigenic mimicry of HTLV proteins extends to other nonplasmodial antigens as well. 相似文献
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Spontaneous leiomyosarcomas of the mouse urinary bladder have not been reported. Data from 8 chronic toxicity/oncogenicity studies that included 400 male and 400 female mice were reviewed and evaluated to gather information on spontaneously occurring urinary bladder leiomyosarcomas. Three control mice from 3 different studies had leiomyosarcomas in the submucosa of the trigone area of the urinary bladder. These tumors were not connected to the surface epithelium; however, they were connected to and destroyed the smooth muscle layer of the urinary bladder. This communication describes the incidence and histopathological features of these neoplasms. 相似文献
67.
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69.
Alterations in galectin-3 expression and distribution correlate with breast cancer progression: functional analysis of galectin-3 in breast epithelial-endothelial interactions 下载免费PDF全文
Shekhar MP Nangia-Makker P Tait L Miller F Raz A 《The American journal of pathology》2004,165(6):1931-1941
To define the role of galectin-3 in breast cancer progression, we have used a novel three-dimensional co-culture system that recapitulates in vivo reciprocal functional breast epithelial-endothelial cell-cell and cell-matrix interactions, and examined the expression of galectin-3 mRNA and protein in human breast tumors and xenografts. Galectin-3 is required for the stabilization of epithelial-endothelial interaction networks because immunoneutralization with galectin-3 antibodies abolishes the interactions in a dose-dependent manner. Co-culture of epithelial cells with endothelial cells results in increase in levels of secreted galectin-3 and presence of proteolytically processed form of galectin-3 in the conditioned media. In contrast, intracellular galectin-3 predominantly exists in the intact form. This difference in sensitivity to proteolytic processing of secreted versus intracellular galectin-3 probably arises from differences in accessibility of protease-sensitive sites, levels, and/or type of activated protease(s), and may be indicative of different functional roles for intact and processed galectin-3. To determine whether the proteolytically cleaved galectin-3 retains its ability to bind to endothelial cells, binding assays were performed with the full-length and matrix metallopeoteinase-2-cleaved recombinant galectin-3. Although a dose-dependent increase in binding to human umbilical vein endothelial cells was observed with both full-length and cleaved galectin-3, proteolytically cleaved galectin-3 displayed approximately 20-fold higher affinity for human umbilical vein endothelial cells as compared to the full-length protein. Examination of galectin-3 expression in breast tumors and xenografts revealed elevated levels of galectin-3 mRNA and protein in the luminal epithelial cells of normal and benign ducts, down-regulation in early grades of ductal carcinoma in situ (DCIS), and re-expression in peripheral tumor cells as DCIS lesions progressed to comedo-DCIS and invasive carcinomas. These data suggest that galectin-3 expression is associated with specific morphological precursor subtypes of breast cancer and undergoes a transitional shift in expression from luminal to peripheral cells as tumors progressed to comedo-DCIS or invasive carcinomas. Such a localized expression of galectin-3 in cancer cells proximal to the stroma could lead to increased invasive potential by inducing novel or better interactions with the stromal counterparts. 相似文献
70.
Incidence of the Carnation etched ring virus (CERV), the only DNA virus reported to date on carnation, was investigated by a bioassay using a partially purified virus as inoculum and then by a double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA). Out of 61 carnation cultivars analyzed 41 (67%) were found positive. The virus positivity was verified by polymerase chain reaction (PCR) and nucleotide sequencing. The amplified 1349 bp fragment was by about 98% and 96% identical with respect to coat protein (CP) and enzymatic polyprotein genes, respectively, as compared to the sequences available in the database. In terms of amino acid sequence similarity, the homology values were 99% and 97%, respectively. Comparison with other caulimoviruses revealed that CERV is most closely related to the Cauliflower mosaic virus (CaMV). High genetic stability of CERV may be attributed to the fact that it has evolved from the same initial sequence in an original host. Because of global market of cut flowers and vegetative propagation it has been dispersed around the world. 相似文献