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21.
22.
DNA microarray analysis reveals novel gene expression profiles in collagen-induced arthritis 总被引:4,自引:0,他引:4
Thornton S Sowders D Aronow B Witte DP Brunner HI Giannini EH Hirsch R 《Clinical immunology (Orlando, Fla.)》2002,105(2):155-168
Global gene expression was analyzed in early and late collagen-induced arthritis (CIA). Of 8734 cDNAs analyzed, 330 were induced and 55 downregulated greater than twofold in early or late disease. Hierarchical clustering of these 385 cDNAs demonstrated five distinct expression patterns differentiating early from late disease and correlating with histopathologic changes in the paw. Of the 385 cDNAs, 185 are known, characterized genes, the majority of which are not described as playing a role in arthritis. However, several of these genes are involved in pathological processes relating to arthritis, including apoptosis, inflammation, and cellular proliferation. One interesting gene, follistatin-like gene, is highly expressed along the margin of contact between inflammatory synovial pannus and eroding bone, suggesting a role in joint destruction. These results demonstrate that global gene expression profiles distinguish early and late CIA and reveal several genes novel to arthritis the further characterization of which will advance our understanding of arthritis. 相似文献
23.
Summary Induction of microtubulin paracrystals (Pc) by Kunjin (KUN) virus occurred after 15 hours post-infection and were often associated with convoluted membranes (cm) and virus particles. Vinblastine sulphate which disrupts microtubulin, had an inhibitory effect on the virus production when added during the viral latent period. When infected samples were extracted with Triton X-100 and analysed by SDS-PAGE, four viral proteins were observed. 相似文献
24.
Sarraf S Tejada R Abawi M Oberst M Dennis T Simon KC Blancato J 《Cancer Genetics and Cytogenetics》2005,161(1):63-69
Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line. 相似文献
25.
Beyer LA Odeh H Probst FJ Lambert EH Dolan DF Camper SA Kohrman DC Raphael Y 《Journal of neurocytology》2000,29(4):227-240
The shaker 2 (sh2) and pirouette (pi) mouse mutants display severe inner ear dysfunction that involves both auditory and vestibular manifestation. Pathology of the stereocilia of hair cells has been found in both mutants. This study was designed to further our knowledge of the pathological characteristics of the inner ear sensory epithelia in both the sh2 and pi strains. Measurements of auditory brainstem responses indicated that both mutants were profoundly deaf. The morphological assays were specifically designed to characterize a pathological actin bundle that is found in both the inner hair cells and the vestibular hair cells in all five vestibular organs in these two mutants. Using light microscope analysis of phalloidin-stained specimens, these actin bundles could first be detected on postnatal day 3. As the cochleae matured, each inner hair cell and type I vestibular hair cell contained a bundle that spans from the region of the cuticular plate to the basal end of the cell, then extends along with cytoplasm and membrane, towards the basement membrane. Abnormal contact with the basement membrane was found in vestibular hair cells. Based on the shape of the cellular extension and the actin bundle that supports it, we propose to name these extensions cytocauds. The data suggest that the cytocauds in type I vestibular hair cells and inner hair cells are associated with a failure to differentiate and detach from the basement membrane. 相似文献
26.
A-kinase anchoring proteins (AKAPs) constitute a family of scaffolding proteins that bind the regulatory subunits of protein kinase A (PKA). AKAP binding to PKA regulates the phosphorylation of various proteins, some of which have been implicated in synaptic plasticity and memory consolidation. Here we show that the regulatory subunits of PKA are colocalized with AKAP150 (an AKAP isoform that is expressed in the brain) in the lateral amygdala (LA) and that infusion to the LA of the peptide St-Ht31, which blocks PKA anchoring onto AKAPs, impairs memory consolidation of auditory fear conditioning. 相似文献
27.
Ernesto Mendes Açucena Raphael Norma G.S. Mota Nelson F. Mendes 《The Journal of allergy and clinical immunology》1974,53(4):223-229
Eighty-nine patients with leprosy, 65 classified as lepromatous and 24 as tuberculoid, were examined in this study. Skin test responses to protein antigens and dinitrochlorobenzene (DNCB) were depressed in lepromatous patients compared to controls. Tuberculoid patients did not exhibit a significant depression to microbial antigens, but they showed a definite depression in the ability to be sensitized with DNCB. The transfer of delayed hypersensitivity reactions to tuberculin, trichophytin, and lepromin (Fernandez and Mitsuda reactions) was accomplished in lepromatous and indeterminate leprosy patients using viable lymphocytes from donors presenting positive reactions to these antigens. The lepromin reaction was also transferred to patients with South American blastomycosis and cutaneous leishmaniasis. The positive reactions of adoptive immunity were confirmed by histologic examination of skin biopsies. 相似文献
28.
Staphylococcal toxic shock syndrome toxin 1-induced tumor necrosis factor alpha and interleukin-1 beta secretion by human peripheral blood monocytes and T lymphocytes is differentially suppressed by protein kinase inhibitors. 下载免费PDF全文
The signal transduction pathways by which staphylococcal toxic shock syndrome toxin 1 (TSST-1) induces tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion were examined with various protein kinase inhibitors. TNF-alpha secretion by normal human monocytes and T cells in response to TSST-1 was suppressed by inhibitors of protein kinase C (H7) and tyrosine kinases (genistein). In contrast, the secretion of IL-1 beta was blocked by a cyclic AMP- and cyclic GMP-dependent kinase inhibitor (HA1004) as well as by H7 and genistein. These results suggest that the secretion of TNF-alpha and IL-1 beta may be differentially regulated by TSST-1 and that protein kinases play an important role in mediating cytokine responses to the toxin. 相似文献
29.
Evidence for supporting cell mitosis in response to acoustic trauma in the avian inner ear 总被引:8,自引:0,他引:8
Y. Raphael 《Journal of neurocytology》1992,21(9):663-671
Summary Acoustic overstimulation can lead to sensory cell (hair cell) loss in the auditory epithelium. Damaged hair cells in the organ of Corti (the mammalian auditory end-organ) degenerate and are replaced by non-sensory cells (supporting cells) which construct an irreversible scar. In birds, however, auditory hair cells which are damaged by acoustic trauma or ototoxic drugs may be replaced by new hair cells. As first step in determining the mechanism of hair cell regeneration, we developed an assay for cell divisions in the auditory epithelium after acoustic trauma. The results of these experiments demonstrate that supporting cells in damaged regions of the auditory epithelium incorporate the DNA-specific marker bromodeoxyuridine as early as one day after noise exposure. We provide direct evidence that following acoustic insult to the avian inner ear, supporting cells which reside within the sensory epithelium divide near the luminal surface and repopulate the epithelium. These results suggest that supporting cells participate in scar formation during hair cell degeneration, and produce new cells for regeneration. 相似文献
30.
Crowding can substantially affect the transition of a protein between its native (N) and unfolded (U) states via volume exclusion
effects. Also, it influences considerably the aggregation (A) of unfolded proteins. To examine the details, we developed an
approach for computing the kinetic rates of the process N ↔ U → A in which the concentration of the protein is explicitly
taken into account. We then compute the relative change with temperature of the protein denaturation for various fractional
volume occupancies and partition of proteins in solution. The analysis indicates that, in protein solutions in which the average
distance between proteins is comparable with the radius of gyration of an unfolded protein, steric effects increase the stability
of the proteins which are in compact, native states. In heterogeneous protein solutions containing various types of proteins
with different thermal stabilities, the unfolding of the most thermolabile proteins will increase the stability of the other
proteins. The results shed light on the way proteins change the thermal stability of a cell as they unfold and aggregate.
This study may be valuable in questions related to the dynamics of thermal injuries. 相似文献