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71.
72.
Celecoxib-induced apoptosis in rat cholangiocarcinoma cells mediated by Akt inactivation and Bax translocation 总被引:16,自引:0,他引:16
Recently, we demonstrated that the cyclooxygenase-2 (COX-2) inhibitor celecoxib acts to significantly suppress the growth of rat C611B cholangiocarcinoma (ChC) cells in vitro. To establish a molecular mechanism for this growth suppression, we investigated the effects of celecoxib on apoptotic signaling pathways in cultured rat C611B ChC cells. Celecoxib and another COX-2 inhibitor, rofecoxib, at 5 microM were almost equally effective in inhibiting prostaglandin E(2) (PGE(2)) production by these cells, but at this low concentration, neither inhibitor suppressed growth or induced apoptosis. Celecoxib at 50 microM induced prominent apoptosis in these cells, whereas rofecoxib at 50 microM was without effect in either suppressing growth or inducing apoptosis. Celecoxib (50 microM) did not alter Bcl-2, Bcl-x(L), or COX-2 protein levels, nor did it inhibit p42/44 mitogen-activated protein kinase (MAPK) phosphorylation; however, it significantly suppressed serine/threonine kinase Akt/PKB (Akt) phosphorylation and kinase activity in cultured C611B cells. This effect, in turn, directly correlated with Bax translocation to mitochondria, cytochrome c release into cytosol, activation of caspase-9 and caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP). Addition of 25 microM PGE(2) to C611B cell cultures blocked the apoptotic actions of celecoxib. Rofecoxib (50 microM) was without effect in suppressing Akt phosphorylation and caspase-3 activation. In vivo, celecoxib partially suppressed tumorigenic growth of C611B ChC cells. In conclusion, our results indicate that celecoxib preferentially acts in vitro to induce apoptosis in ChC cells through a mechanism involving Akt inactivation, Bax translocation, and cytochrome c release. Our in vivo results further suggest celecoxib might have potential therapeutic or chemopreventive value against ChC. 相似文献
73.
A single recombinant anti-RhD IgG prevents RhD immunization: association of RhD-positive red blood cell clearance rate with polymorphisms in the FcgammaRIIA and FcgammaIIIA genes 下载免费PDF全文
Miescher S Spycher MO Amstutz H De Haas M Kleijer M Kalus UJ Radtke H Hubsch A Andresen I Martin RM Bichler J 《Blood》2004,103(11):4028-4035
A single recombinant immunoglobulin G1 (IgG1) anti-RhD antibody (MonoRho) was compared with a currently used polyclonal anti-RhD product (Rhophylac) in a phase 1 study for safety, efficacy of Rhesus D (RhD)-positive red blood cell (RBC) clearance, and prevention of RhD immunization in RhD-negative men challenged with 15 mL RhD-positive RBCs. Both the polyclonal product and recombinant anti-RhD effectively cleared RhD-positive RBCs after intravenous and intramuscular injection. The recombinant anti-RhD demonstrated a slower clearance rate compared with the polyclonal anti-RhD. There was no dose response, and there was considerable variation among subjects who received the same dose of recombinant anti-RhD. Interestingly, RhD-positive RBC clearance rates were strongly associated with Fcgamma receptor IIA (FcgammaRIIA) and FcgammaIIIA but not with FcgammaIIIB polymorphisms. Subjects homozygous for FcgammaRIIA-131H or FcgammaRIIIA-158V allotypes showed a faster clearance rate compared with both the heterozygote and the corresponding alternative homozygote allotypes. A similar but less marked trend was seen for the polyclonal anti-RhD. Despite the variation in clearance rates there was no evidence of anti-RhD alloantibodies in any of the subjects at +6 months after the RBC challenge. 相似文献
74.
Laminar specificity of intrinsic connections in Broca's area 总被引:1,自引:0,他引:1
Broca's area and its right hemisphere homologue comprise 2 cytoarchitectonic subdivisions, FDgamma and FCBm of von Economo C and Koskinas GN (1925, Die Cytoarchitektonik der Hirnrinde des erwachsenen Menschen. Vienna/Berlin [Germany]: Springer). We report here on intrinsic connections within these areas, as revealed with biotinylated dextran amine and 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate tracing in postmortem human brains. Injections limited to supragranular layers revealed a complex intrinsic network of horizontal connections within layers II and III spreading over several millimeters and to a lesser extent within layers IV, V, and VI. Ninety percent of the retrogradely labeled neurons (n = 734) were in supragranular layers, 4% in layer IV, and 6% in infragranular layers; most were pyramids and tended to be grouped into clusters of approximately 500 microm in diameter. Injections involving layer IV revealed extended horizontal connections within layers I-IV (up to 3.7 mm) and to a lesser extent in layers V and VI. Injections limited to the infragranular layers revealed horizontal connections mainly limited to these layers. Thus, intrinsic connections within Broca's area display a strong laminar specificity. This pattern is very similar in areas FDgamma and FCBm and in the 2 hemispheres. 相似文献
75.
BACKGROUND: Solvent/detergent (S/D) inactivates enveloped viruses in plasma. The current technology requires a plasma fractionation facility and is applied to large plasma pools, which increases the cost and risks of exposure to S/D-resistant pathogens and lowers the content of protein S and alpha2-antiplasmin. Two S/D treatment procedures for single donations or minipools of plasma have been developed with a single-use bag system. STUDY DESIGN AND METHODS: Frozen plasma samples were thawed and treated in disposable bags with either 2 percent tri(n-butyl)phosphate (TnBP) at 37 degrees C or 1 percent TnBP and 1 percent Triton X-45 at 31 degrees C for 4 hours. Plasma samples were extracted three times with 7.5 percent sterile castor oil to remove TnBP and Triton X-45. The TnBP-treated plasma samples were further subjected to a clarifying centrifugation (3800 x g, 30 min). Final plasma samples were dispensed into individual bags and frozen at -30 degrees C. Plasma quality was assessed at each step of the procedures. RESULTS: Both processes yielded greater than 90 percent mean recovery of coagulation factors (clottable fibrinogen, von Willebrand factor, and factors VIII, V, VII, IX, X, and XI), anticoagulants (protein C, protein S), protease inhibitors (antithrombin, alpha2-antiplasmin), total protein, albumin, and immunoglobulins. Global coagulation tests of the treated plasma samples were normal. Final TnBP and Triton X-45 content was less than 10 and 50 ppm, respectively. CONCLUSION: S/D treatment of plasma can be performed in a closed-bag system under conditions that maintain plasma protein quality. The technology is simple, presents advantages over the industrial large-scale S/D plasma process, and could be performed in blood centers. 相似文献
76.
Sirima SB Cotte AH Konaté A Moran AC Asamoa K Bougouma EC Diarra A Ouédraogo A Parise ME Newman RD 《The American journal of tropical medicine and hygiene》2006,75(2):205-211
The World Health Organization recommends that pregnant women in malaria-endemic areas receive >or= 2 doses of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp/SP) in the second and third trimesters of pregnancy to prevent maternal anemia, placental parasitemia, and low birth weight (LBW). In 2001, a program evaluation in Koupéla District, Burkina Faso demonstrated that despite widespread use of chloroquine chemoprophylaxis, the burden of malaria during pregnancy remained high. In 2003, the Burkina Faso Ministry of Health piloted a program of IPTp/SP (three doses) and accelerated distribution of insecticide-treated nets (ITN) to pregnant women in Koupéla District. In 2004, a follow-up program evaluation was conducted. Coverage with >or= 1 doses of IPTp/SP was high among women attending antenatal clinics (ANCs) (96.2%) and delivery units (DUs) (93.5%); ITN ownership was moderately high (ANC = 53.9%, DU = 61.6%). In multivariate analysis, >or= 1 dose of IPTp/SP was associated with a significant reduction in the prevalence of peripheral parasitemia at ANCs (risk ratio [RR] = 0.49, P = 0.008), >or= 2 doses of IPTp/SP were associated with a reduction in the prevalence of placental parasitemia (RR = 0.56, P = 0.02), and three doses of IPTp/SP were associated with a reduced risk of LBW (RR = 0.51, P = 0.04). The proportions of women at ANCs with peripheral parasitemia and anemia were significantly lower in 2004 than in 2001 (RR = 0.53, P = 0.001 and RR = 0.78, P = 0.003, respectively). The proportions of women at DUs with peripheral and placental parasitemia were also significantly lower in 2004 than in 2001 (RR = 0.66, P < 0.0001 and RR = 0.71, P = 0.0002, respectively). These data suggest that a package of IPTp/SP and ITNs is effective in reducing the burden of malaria during pregnancy in Burkina Faso. 相似文献
77.
Poklis JL Thompson CC Long KA Lichtman AH Poklis A 《Journal of analytical toxicology》2010,34(8):516-520
A liquid chromatography-tandem mass spectrometry (LC-MS-MS)method was developed for the analysis of marijuana cannabinoids in mouse brain tissue using an Applied Biosystems 3200 Q trap with a turbo V source for TurbolonSpray attached to a Shimadzu SCL HPLC system. The method included cannabichromene (CBC),cannabidiol (CBD), Δ?-tetrahydrocannabinol (THC), 11-hydroxytetrahydrocannabinol (11-OH-THC), and 11-nor-Δ?-tetrahydrocannabinol-9-carboxylic acid (THC-COOH). These compounds were isolated by liquid-liquid extraction using cold acetonitrile. The following transition ions were monitored by multiple reaction monitoring (MRM): m/z 315>193, 315>259 for THC/CBD/CBC; m/z 331>193, 331>105 for 11-OH-THC; m/z 345>299, 345>193 for THC-COOH; m/z 318>196 for THC-d?; m/z 334>196 for 11-OH-THC-d?, and m/z 348>302 for THC-COOH-d?. Linearity for THC, 1-OH-THC, and THC-COOH was 1-200 ng/g; for CBC and CBD, it was 0.5-20 ng/g. Within-run and between-run precisions for all the analytes yielded coefficients of variation of < 20%. Four C57BL6 mice were sacrificed 20 min after nose-only exposure to the smoke of 200 mg of marijuana containing 0.44 mg CBC, 0.93 mg CBD, and 8.81 mg THC. The mean brain concentrations were 3.9 ± 1.5 ng/g CBC, 21 ± 3.9 ng/g CBD, 364 ± 74 ng/g THC, and 28 ± 5.9 ng/g 11-OH-THC. THC-COOH was not detected. The relative mean brain cannabinoid concentrations correlated to the amounts of the cannabinoids in the inhaled marijuana. 相似文献
78.
Ritter JK Li C Xia M Poklis JL Lichtman AH Abdullah RA Dewey WL Li PL 《The Journal of pharmacology and experimental therapeutics》2012,342(3):770-779
Medullipin has been proposed to be an antihypertensive lipid hormone released from the renal medulla in response to increased arterial pressure and renal medullary blood flow. Because anandamide (AEA) possesses characteristics of this purported hormone, the present study tested the hypothesis that AEA or one of its metabolites represents medullipin. AEA was demonstrated to be enriched in the kidney medulla compared with cortex. Western blotting and enzymatic analyses of renal cortical and medullary microsomes revealed opposite patterns of enrichment of two AEA-metabolizing enzymes, with fatty acid amide hydrolase higher in the renal cortex and cyclooxygenase-2 (COX-2) higher in the renal medulla. In COX-2 reactions with renal medullary microsomes, prostamide E2, the ethanolamide of prostaglandin E(2), was the major product detected. Intramedullarily infused AEA dose-dependently increased urine volume and sodium and potassium excretion (15-60 nmol/kg/min) but had little effect on mean arterial pressure (MAP). The renal excretory effects of AEA were blocked by intravenous infusion of celecoxib (0.1 μg/kg/min), a selective COX-2 inhibitor, suggesting the involvement of a prostamide intermediate. Plasma kinetic analysis revealed longer elimination half-lives for AEA and prostamide E2 compared with prostaglandin E(2). Intravenous prostamide E2 reduced MAP and increased renal blood flow (RBF), actions opposite to those of angiotensin II. Coinfusion of prostamide E2 inhibited angiotensin II effects on MAP and RBF. These results suggest that AEA and/or its prostamide metabolites in the renal medulla may represent medullipin and function as a regulator of body fluid and MAP. 相似文献
79.
Senescence is the result of an imbalance between free radical production and antioxidant defenses, with concomitant oxidative stress and age-dependent functional decline. This process is especially evident in the immune cells, which use free radicals in their functions and suffer a senescent deterioration probably linked to oxygen stress. We hypothesize that oxidative damage and antioxidant imbalance may play a critical role in the immune dysfunction in aging. In the present study, we investigated this hypothesis in aged rats by treatment with alpha-lipoic acid (α-LA). We studied the effect of α-LA on immune function by examining immunomodulating factors in the plasma. Then we examined oxidative damage and antioxidant defense systems in the plasma. We found out that immune dysfunction in aged animals is associated with increased oxidative damage and decreased antioxidant status and treatment with α-LA effectively elevated immune function, decreased oxidative insult and enhanced antioxidant status. These results suggest that α-LA may be effective in improving immune function in aging through decreasing oxidative damage and revitalizing antioxidants in blood. 相似文献