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81.
Poornima Bhat-Nakshatri Hitesh Appaiah Christopher Ballas Patricia Pick-Franke Robert GouletJr Sunil Badve Edward F Srour Harikrishna Nakshatri 《BMC cancer》2010,10(1):411
Background
Breast cancer cells with CD44+/CD24- cell surface marker expression profile are proposed as cancer stem cells (CSCs). Normal breast epithelial cells that are CD44+/CD24- express higher levels of stem/progenitor cell associated genes. We, amongst others, have shown that cancer cells that have undergone epithelial to mesenchymal transition (EMT) display the CD44+/CD24- phenotype. However, whether all genes that induce EMT confer the CD44+/CD24- phenotype is unknown. We hypothesized that only a subset of genes associated with EMT generates CD44+/CD24- cells. 相似文献82.
Identification of CpG oligonucleotide sequences with high induction of IFN-alpha/beta in plasmacytoid dendritic cells. 总被引:20,自引:0,他引:20
A Krug S Rothenfusser V Hornung B Jahrsd?rfer S Blackwell Z K Ballas S Endres A M Krieg G Hartmann 《European journal of immunology》2001,31(7):2154-2163
The immature plasmacytoid dendritic cell (PDC) is identical with the principal type I IFN-producing cell upon viral infection. Oligodeoxynucleotides which contain unmethylated CpG motifs (CpG ODN) are recognized by the vertebrate immune system. Previously, we described CpG ODN that strongly activate human B cells and human blood dendritic cells. Here we describe distinct CpG-containing oligonucleotide sequences which, in contrast to previously described CpG ODN, induced high amounts of IFN-alpha and IFN-beta in peripheral blood mononuclear cells (PBMC). Intracellular staining for IFN-alpha revealed that within PBMC CpG ODN-induced IFN-alpha is produced exclusively by PDC. Unlike IFN-alpha, TNF-alpha is up-regulated in PDC by all CpG ODN tested. Purified PDC responded to CpG ODN, demonstrating direct activation of PDC by CpG ODN. The most active sequence induced the production of up to 5 pg IFN-alpha per single PDC, resulting in more than 400 ng/ml IFN-alpha in the supernatant of PBMC enriched for PDC. The potency of CpG ODN to stimulate IFN-alpha correlated with their ability to stimulate NK cell lytic activity, while purified NK cells did not respond to CpG ODN. IFNgamma production in PBMC was dependent on CpG ODN-induced IFN-alpha/beta as demonstrated by IFN-alpha/beta blocking antibodies. IFN-alpha-inducing CpG ODN strongly supported IFN-gamma production of TCR-triggered CD4 T cells but were less active than other CpG ODN in stimulating B cells. In conclusion our results demonstrate that particular CpG ODN sequences exist which, due to high IFN-alpha/beta induction in PDC, induce a set of immune responses typical for viral infection. 相似文献
83.
P J Green S K Ballas P Westkaemper H G Schwartz T L Klug V R Zurawski 《Journal of the National Cancer Institute》1986,77(2):337-341
CA 19-9 and CA 125 serum levels were evaluated among smoking and nonsmoking healthy blood donors. Smoking did not elevate mean levels of either CA 19-9 or CA 125 in the sera of 496 of these blood donors from Philadelphia, PA. Mean CA 19-9 levels were slightly higher among females than among males. Among smokers there was a trend toward slightly increasing CA 19-9 serum levels with increased age, which was significant among the male donors. Trends toward slightly decreased mean serum levels of CA 125 among smokers were of borderline significance. Serum CA 19-9 and CA 125 levels in none of these donor subpopulations was elevated compared to levels reported by others for gastrointestinal or ovarian carcinoma patients, respectively. Therefore, smoking status should not interfere with use of either the CA 19-9 or CA 125 assays for diagnostic or monitoring applications. 相似文献
84.
85.
Bernard L. Lopez Jordan Barnett Samir K. Ballas Theodore A. Christopher Linda Davis-Moon Xin-liang Ma 《Academic emergency medicine》1996,3(12):1098-1102
Objectives: 1) To measure nitric oxide (NO) metabolite levels in patients presenting to the ED in acute vasoocclusive sickle-cell crisis (SCC), and 2) to determine whether a relationship exists between NO metabolite levels and pain. Methods: A prospective, observational study of patients with documented sickle-cell anemia (SCA), aged ±18 years, presenting in typical, acute SCC was conducted in an urban, university teaching hospital. Excluded were those with atypical pain or acute, coexistent disease (as evidenced by fever, tachycardia, tachyon, or hypotension). Pain scores were measured by a 10-cm visual analog scale (VAS). Blood NO metabolite levels for SCC patients and control subjects (healthy volunteers, n = 9; SCA control subjects not in SCC, n = 10) were determined using an NO-specific chemiluminescence technique that measured plasma nitrite and nitrate, the stable end-products of NO. The acute SCC patients were divided into 3 groups, with the range for the SCC-normal (n = 5) group defined as within 2 SD of the healthy volunteer control patients. The SCC-low patients (n = 21) had NO metabolite levels below this range and the SCC-high (n = 21) patients had levels above this range. Results: The SCA and healthy volunteer control groups had similar NO metabolite levels (25.3 vs 22.6 μmol; p = 0.10). The 3 acute SCC groups had the following mean NO levels: 1) SCC-normal = 21.3 ± 1.6 μmol; 2) SCC-low = 7.2 ± 1.1 μmol; and 3) SCC-high = 43.7 ± 3.5 μmol. The SCC-high NO-level group had significantly lower VAS pain scores when compared with the SCC-low and SCC-normal NO-level groups (6.52 ± 1.85 cm vs 8.76 ± 0.83 cm, and 8.62 ± 1.29 cm, p = 0.02). Conclusion: NO metabolite levels vary in SCC patients. Elevated levels are associated with lower pain scores, while lower levels are associated with higher pain scores, indicating that NO metabolites may potentially represent a marker for compensatory mechanisms in SCC tissue ischemia. Further work is needed to delineate the usefulness of NO metabolites in assessing the seventy of SCC. 相似文献
86.
The purpose of the present study was to investigate the effect of alpha-thalassemia on the prevalence of avascular necrosis in 52 adult patients with sickle cell anemia. alpha-Globin genotypes were determined by restriction endonuclease mapping of genomic DNA extracted from peripheral blood leukocytes. Radiographs of humeral and femoral heads were interpreted by two radiologists who were not aware of the clinical picture and the genotype of the patients in the study. We present data showing that there is a significant positive correlation between alpha-gene deletion and the prevalence and extent of avascular necrosis in our patient population. 相似文献
87.
O E Jaschevatzky S Dascalu Y Noy R P Rosenberg S Anderman S Ballas 《Obstetrics and gynecology》1992,79(1):32-34
Intrauterine prostaglandin (PG) F2 alpha infusion and intravenous (IV) oxytocin infusion were compared to evaluate the effectiveness of the two methods for termination of pregnancies with second-trimester rupture of membranes. Twenty-two women with this complication were randomly allocated to receive either 20 mg PGF2 alpha, diluted in 500 mL of NaCl 0.9% and administered through a Foley catheter inserted through the cervix, or IV oxytocin infusion in increasing doses. All subjects in the PGF2 alpha group aborted after the first administration. Repeat infusion was necessary in three oxytocin-treated subjects. The mean (+/- SD) induction-abortion interval was significantly shorter in those receiving PGF2 alpha (6.7 +/- 1.2 hours) than in those receiving oxytocin (8.8 +/- 2.7 hours). Minor side effects, such as nausea and vomiting, were observed in three women during PGF2 alpha infusion and were treated symptomatically and by temporary interruption of the infusion. Uterine hypertonus, observed in one subject in each group, was treated by temporary cessation of the infusion. We conclude that intrauterine PGF2 alpha infusion seems more effective than IV oxytocin for termination of pregnancies with second-trimester rupture of membranes. 相似文献
88.
Retinal terminals in the pretectum were labelled by anterograde axonal transport of horseradish peroxidase (HRP) after injecting the enzyme into one eye. Pretectal neurons were retrogradely labelled by HRP-injections into the dorsal cap of the inferior olive. Electrophysiological recordings were performed in the same animal. This procedure showed that direction-selective neurons in the nucleus of the optic tract (NOT) projecting to the dorsal cap of the inferior olive lie dorsal and lateral to the retinal terminal clusters. Direction-unselective neurons sensitive to high stimulus velocities (jerk-neurons) were localized within the areas of retinal terminal clusters. Both jerk-neurons and retinal terminal clusters never overlapped with retrogradely labelled neurons. Latency measurements to stimulation of the optic chiasm (OX) confirmed a monosynaptic W-cell projection to the direction-selective NOT cells and indicated a predominantly monosynaptic Y-cell projection to the jerk-neurons. 相似文献
89.
90.
Purpose: To determine if the pattern of release of neurotensin from the enkephalin-, neurotensin- and somatostatin-like immunoreactive amacrine cells in response to light and dark is the same as that of the enkephalins and somatostatin. Methods/Results: Both the enkephalins and somatostatin are released at high rates in the dark and at lower rates in the light, and these rate changes are reflected in increasing intracellular levels of the peptides in vivo in the light and decreasing levels in the dark The levels of neurotensin-like immunoreactivity show a similar diurnal light-driven and non-circadian rhythm in vivo. Conclusion: This implies that the actual release rates of neurotensin follow the same patterns as those demonstrated in vitro for the enkephalins and somatostatin. 相似文献