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31.
Some determinants of the locomotory behaviour of phagocytes and lymphocytes in vitro 总被引:2,自引:0,他引:2
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In this review, we discuss some physical and chemical determinants of locomotor behaviour of phagocytic cells and lymphocytes as studied in visual assays, paying particular attention to the following points. (a) A distinction is made between chemokinesis and other forms of kinesis. We propose that the term chemokinesis be reserved for responses resulting from selective recognition of chemical substances. Many kineses in leucocytes may not involve such recognition, but may result from a variety of physical factors, such as those that alter the adhesiveness between cell and substratum. (b) Neutrophils moving in aligned gels of collagen or fibrin show contact guidance of locomotion, i.e. bidirectional movement along the axis of alignment of the fibres of the gel. Thus neutrophils show directional locomotion not only in chemotactic gradients but also in response to physical properties of the substratum. (c) Lymphocytes adhere poorly and move poorly on 2D protein coated substrata. However they move rapidly through 3D collagen gels. This locomotion may be independent of adhesion since lymphocytes may gain traction for locomotion by expanding pseudopods into gaps in the gel matrix, then using the pseudopod as an anchor for subsequent locomotion in any direction. 相似文献
32.
Intestinal hypersensitivity reactions in the rat. I. Uptake of intact protein, permeability to sugars and their correlation with mucosal mast-cell activation.
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M W Turner P Boulton J G Shields S Strobel S Gibson H R Miller R J Levinsky 《Immunology》1988,63(1):119-124
We have confirmed previous observations that intestinal anaphylaxis induced in rats previously sensitized to ovalbumin (OVA) is associated with an increased uptake of an unrelated 'bystander' protein, bovine serum albumin (BSA) fed 1 hr previously. In this study, this enhanced protein uptake was associated with an increased lactulose/rhamnose excretion ratio after administration of these sugars, although there was no correlation between the two measurements. One hour after antigen challenge the serum levels of rat mast-cell protease II (RMCPII), a specific marker for mucosal mast-cell secretion, were significantly higher than both the pre-challenge levels and those of sham-challenged controls (P less than 0.002). There was a significant positive correlation between the serum levels of RMCPII and the lactulose/rhamnose excretion ratios (P less than 0.05), but no such correlation existed between RMCPII and BSA levels in the challenged rats. In other studies the urinary lactulose/rhamnose ratios of rats with cetrimide-induced gut damage were found to be significantly increased, although BSA uptake into the serum remained unaltered. We conclude that there is no simple correlation between gut permeation of low-molecular weight sugars and and the uptake of macromolecular proteins. 相似文献
33.
Shields CM Taylor R Nazarenus T Cheatle J Hou A Tapprich A Haifley A Atkin AL 《Current genetics》2003,44(4):184-194
Saccharomyces cerevisiae ATS1 (-tubulin suppressor 1) was originally identified as a high-copy suppressor of class two -tubulin mutations and was proposed to have a regulatory role in coordinating the microtubule state with the cell cycle. Here, we show that Ats1p interacts with Nap1p, a cytoplasmic protein that regulates the activity of the Cdc28p/Clb2p complex. Loss of Nap1p results in a delayed switch from polar to isotropic bud growth. The delayed switch results in elongated buds. Nap1p and Ats1p interact in two-hybrid and co-immunoprecipitation assays. Both nap1 and ats1 cells have a Clb2p-dependent elongated bud morphology. Deletion of ATS1 partially suppresses the elongated bud morphology and benomyl resistance of nap1 mutants. Our results suggest Ats1p might regulate coordination of the microtubule state with the cell cycle through an interaction with Nap1p.Communicated by S. Hohmann 相似文献
34.
Patrick S Fitch Vanessa Brown Bettina C Schock Madeleine Ennis Michael D Shields 《Annals of allergy, asthma & immunology》2003,90(4):429-433
BACKGROUND: In asthma there is increased expression of the Th2-type cytokine interleukin-4 (IL-4). IL-4 is important in immunoglobulin isotype switching to immunoglobulin E and adhesion of eosinophils to endothelium. OBJECTIVE: We hypothesized that levels of IL-4 in bronchoalveolar lavage (BAL) fluid would be increased in stable, atopic asthmatic children compared with controls and that levels of its physiologic inhibitor IL-4 soluble receptor alpha (IL-4sR alpha) would be correspondingly decreased. METHODS: One hundred sixteen children attending a children's hospital for elective surgery were recruited. A nonbronchoscopic BAL was performed, and IL-4 and IL-4sR alpha were measured in the BAL supernatants. RESULTS: There was no significant difference in IL-4 concentrations between atopic asthmatic children, atopic normal controls, and nonatopic normal controls [0.13 pg/mL (0.13 to 0.87) vs 0.13 pg/mL (0.13 to 0.41) vs 0.13 pg/mL (0.13 to 0.5), P = 0.65]. IL-4sR alpha levels were significantly increased in asthmatic patients compared with atopic controls [6.4 pg/mL (5.0 to 25.5) vs 5.0 pg/mL (5.0 to 9.9), P = 0.018], but not when compared with the nonatopic controls [5.2 pg/mL (5.0 to 10.6), P = 0.19]. CONCLUSIONS: Contrary to expectation, IL-4sR alpha levels are increased in BAL from stable asthmatic children compared with nonatopic controls, and we speculate that IL-4sR alpha is released by inflammatory cells in the airways to limit the proinflammatory effects of IL-4. 相似文献
35.
36.
M J Shields J N Siegel C R Clark K K Hines L A Potempa H Gewurz B Anderson 《Journal of immunological methods》1991,141(2):253-261
The purpose of this study was to compare and contrast two enzyme immunoassay systems: the enzyme-linked immunosorbent assay (ELISA), which utilizes polystyrene microtiter plates as the adsorptive surface and the enzyme-linked immunoflow assay (ELIFA), which utilizes nitrocellulose membranes. The principal parameter under scrutiny was the denaturing or unfolding effects caused by the interaction of the protein with the adsorptive surfaces in each assay system. These effects were monitored by utilizing two conformationally distinct forms of human C-reactive protein (CRP), the native form of CRP and a denatured form (M-CRP), with a corresponding panel of monoclonal antibodies (MAbs) specific to either CRP or M-CRP. The results show that the ELIFA system was less sensitive than the ELISA system but that the ELIFA assay can be completed in less time than the ELISA. Also, adsorption of native CRP to the polystyrene surface in the ELISA system resulted in conformational changes of the adsorbed native CRP protein such that M-CRP reactive determinants were available for binding with anti-M-CRP MAbs, whereas native CRP adsorbed to the nitrocellulose membrane in the ELIFA system resulted in very limited conversion of CRP to M-CRP reactive epitopes. These results have important implications for development of immunoassays and screening of MAbs for proteins whose conformations may be affected by adsorption to various surfaces. 相似文献
37.
38.
Mohan Srivarshini Cherukupalli Walcott-Sapp Sarah Lee Minna K. Srour Marissa K. Kim Sungjin Amersi Farin F. Giuliano Armando E. Chung Alice P. 《Annals of surgical oncology》2021,28(11):5907-5917
Annals of Surgical Oncology - Biomarker changes in patients with residual disease (RD) after neoadjuvant systemic therapy (NAT) have unclear consequences. This study examined the prevalence of... 相似文献
39.
Ashley D. Marumoto MD Srivarshini C. Mohan MD Stephanie A.K. Angarita MD Marissa K. Srour MD Vicky E. Norton Farnaz Dadmanesh MD Armando E. Giuliano MD 《The breast journal》2021,27(11):828-831
For women with breast cancer in whom multiple Oncotype DX® Recurrence Scores (RS) are obtained, RS concordance utilizing current NCCN recommendations has not been evaluated. Patients with two or more RS were identified. RS were stratified by NCCN guidelines and compared for concordance. Twenty-four patients were evaluated. RS concordance varied by tumor type: 100% in the same tumor, 91.7% in multiple ipsilateral tumors, 71.4% in contralateral tumors, and 66.7% in in-breast recurrent tumors. RS concordance for multiple assays in the same patient is not high enough to omit Oncotype DX® testing for each tumor. 相似文献
40.
Marissa Forbes Blair G Darney Shaalini Ramanadhan Mary Earp Lauren Waldner-James Leo Han 《Contraception》2021,103(4):276-281
ObjectiveWe sought to assess how women interpret the information they find online about the overall safety and risk of infertility associated with abortion and cesarean delivery (CD).MethodsWe conducted an exploratory, prospective study tracking the internet searches of 100 reproductive-aged individuals who identify as women. We directed participants to search for information about either (1) whether surgical abortion or CD is safe or (2) the risk of infertility following surgical abortion or CD. Our data collection had 3 phases: baseline survey, directed internet search, and a postsearch survey. We analyzed participants’ pre- and postsurvey responses using bivariate tests and analyzed within-subject changes. We evaluated the sites they visited based on expert ratings of site content based on trustworthiness and slant.ResultsWomen perceived abortion as safer and less likely to cause infertility after their web searches than before (70% perceived abortion in the United States as very/completely safe presearch vs 92% postsearch; p < 0.02). Women's perceptions about CD did not change. Participants sought information from web pages that experts largely deemed trustworthy and lacking in slant.ConclusionsWomen's perceptions about abortion safety and risk can be influenced by information they find online; perceptions about CD safety and risk may be less influenced by online information.ImplicationsDisseminating high quality, user-friendly abortion information on highly ranked and easily findable websites can help women find evidence-based information and influence knowledge about abortion. 相似文献