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101.
BRCA1 suppresses osteopontin-mediated breast cancer 总被引:4,自引:0,他引:4
El-Tanani MK Campbell FC Crowe P Erwin P Harkin DP Pharoah P Ponder B Rudland PS 《The Journal of biological chemistry》2006,281(36):26587-26601
102.
Whendee L. Silver rew W. Thompson Megan E. McGroddy Ruth K. Varner† Jadson D. Dias‡ Hudson Silva†‡ Patrick M. Crill† Michael Keller§ 《Global Change Biology》2005,11(2):290-306
Fine root dynamics have the potential to contribute significantly to ecosystem‐scale biogeochemical cycling, including the production and emission of greenhouse gases. This is particularly true in tropical forests which are often characterized as having large fine root biomass and rapid rates of root production and decomposition. We examined patterns in fine root dynamics on two soil types in a lowland moist Amazonian forest, and determined the effect of root decay on rates of C and N trace gas fluxes. Root production averaged 229 (±35) and 153 (±27) g m?2 yr?1 for years 1 and 2 of the study, respectively, and did not vary significantly with soil texture. Root decay was sensitive to soil texture with faster rates in the clay soil (k=?0.96 year?1) than in the sandy loam soil (k=?0.61 year?1), leading to greater standing stocks of dead roots in the sandy loam. Rates of nitrous oxide (N2O) emissions were significantly greater in the clay soil (13±1 ng N cm?2 h?1) than in the sandy loam (1.4±0.2 ng N cm?2 h?1). Root mortality and decay following trenching doubled rates of N2O emissions in the clay and tripled them in sandy loam over a 1‐year period. Trenching also increased nitric oxide fluxes, which were greater in the sandy loam than in the clay. We used trenching (clay only) and a mass balance approach to estimate the root contribution to soil respiration. In clay soil root respiration was 264–380 g C m?2 yr?1, accounting for 24% to 35% of the total soil CO2 efflux. Estimates were similar using both approaches. In sandy loam, root respiration rates were slightly higher and more variable (521±206 g C m2 yr?1) and contributed 35% of the total soil respiration. Our results show that soil heterotrophs strongly dominate soil respiration in this forest, regardless of soil texture. Our results also suggest that fine root mortality and decomposition associated with disturbance and land‐use change can contribute significantly to increased rates of nitrogen trace gas emissions. 相似文献
103.
The iron chelators desferrioxamine (DFO), pyridoxal isonicotinoyl hydrazone (PIH), 2,2-bipyridine, diethylenetriamine penta-acetic acid (DTPA) and 1,2 dimethyl-3-hydroxy pyrid-4-one (CP20) were analysed for their ability to change59Fe uptake and release from the brain of 15- and 63-day rats either during or after intravenous injection of59Fe-125I-transferrin. DTPA was the only chelator unable to significantly reduce iron uptake into the brain of 15-day rats. This indicates that iron is not released from transferrin at the luminal surface of brain capillary endothelial cells. CP20 was able to reduce iron uptake in the brain by 85% compared to 28% with DFO. Only CP20 was able to significantly reduce brain iron uptake in 63 day rats. Once59Fe had entered the brain no chelator used was able to mediate its release. All of the chelators except CP20 had similar effects on femur iron uptake as they did on brain uptake, suggesting similar iron uptake mechanisms. It is concluded that during the passage of transferrin-bound iron into the brain the iron is released from transferrin within endothelial cells after endocytosis of transferrin. 相似文献
104.
105.
J.E. Moore A.B. Shaw T. Stanley M.J. Crowe & J.S. Elborn 《Letters in applied microbiology》2001,33(1):82-83
Long-term preservation methods are important in the maintenance of bacteria for downstream research applications. Most clinical laboratories have only limited resources for archiving isolates and therefore require cost-effective and simple methods. An effective and cheap storage method using debrinated blood and maintenance at -80 degrees C is described. 相似文献
106.
Ellery PJ Tippett E Chiu YL Paukovics G Cameron PU Solomon A Lewin SR Gorry PR Jaworowski A Greene WC Sonza S Crowe SM 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(10):6581-6589
HIV-1 persists in peripheral blood monocytes in individuals receiving highly active antiretroviral therapy (HAART) with viral suppression, despite these cells being poorly susceptible to infection in vitro. Because very few monocytes harbor HIV-1 in vivo, we considered whether a subset of monocytes might be more permissive to infection. We show that a minor CD16+ monocyte subset preferentially harbors HIV-1 in infected individuals on HAART when compared with the majority of monocytes (CD14highCD16-). We confirmed this by in vitro experiments showing that CD16+ monocytes were more susceptible to CCR5-using strains of HIV-1, a finding that is associated with higher CCR5 expression on these cells. CD16+ monocytes were also more permissive to infection with a vesicular stomatitis virus G protein-pseudotyped reporter strain of HIV-1 than the majority of monocytes, suggesting that they are better able to support HIV-1 replication after entry. Consistent with this observation, high molecular mass complexes of apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like 3G (APOBEC3G) were observed in CD16+ monocytes that were similar to those observed in highly permissive T cells. In contrast, CD14highCD16- monocytes contained low molecular mass active APOBEC3G, suggesting this is a mechanism of resistance to HIV-1 infection in these cells. Collectively, these data show that CD16+ monocytes are preferentially susceptible to HIV-1 entry, more permissive for replication, and constitute a continuing source of viral persistence during HAART. 相似文献
107.
108.
Huang C Moree WJ Zamani-Kord S Li BF Tucci FC Malany S Wen J Wang H Hoare SR Yang C Madan A Crowe PD Beaton G 《Bioorganic & medicinal chemistry letters》2011,21(3):947-951
Structure-activity relationship studies were conducted to reduce CYP2D6-mediated metabolism in a series of indene H1-antihistamines. Reductions in pKa via incorporation of a β-fluoro substituent or a heteroaryl moiety were shown to reduce contributions to metabolism through this pathway. Several compounds, including 8l, 8o, and 12f were identified with promising primary in vitro profiles and reduced biotransformation via CYP2D6. 相似文献
109.
Background aimsTraumatic injuries of the central nervous system cause damage and degeneration of specific cell populations with subsequent functional loss. Cell transplantation is a strategy to treat such injuries by replacing lost or damaged cell populations. Many kinds of cells are considered candidates for intraspinal transplantation. Human neural precursor cells (hNPC) derived from post-mortem fetal tissue are easy to isolate and expand, and are capable of producing large numbers of neuronal and glial cells. After transplantation into the nervous system, hNPC produce mature neural phenotypes and permit functional improvement in some models of neurodegenerative disease. In this study, we aimed to elucidate the therapeutic effect of different neuronal and glial progenitor populations of hNPC on locomotor and sensory functions of spinal cord-injured (SCI) ratsMethodsDifferent populations of progenitor cells were obtained from hNPC by cell sorting and neural induction, resulting in cell cultures that were NCAM+ A2B5+, NCAM+ A2B5? or A2B5+ NG2+. These different cell populations were then tested for efficacy in repair of the injured spinal cord by transplantation into rats with SCIResultsThe A2B5+ NG2+ population of hNPC significantly improved locomotor and sensory (hindlimb) functional recovery of SCI rats. Importantly, no abnormal pain responses were observed in the forelimbs following transplantationConclusionsThis treatment approach can improve functional recovery after SCI without causing allodynia. Further studies will be conducted to investigate the ability of A2B5+ NG2+ cells to survive, differentiate and integrate in the injured spinal cord. 相似文献
110.