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61.
D. Boerner U. Bicker A. E. Ziegler U. Stosiek H. J. Peters 《Cancer immunology, immunotherapy : CII》1979,6(4):237-242
Summary Patients with different types of cancer received treatment PO or IV with the new immunostimulating compound, 2-[2-cyanaziridinyl-(1)]-2-[2-carbamoylaziridinyl-(1)]-propane, BM 12.531 (Prop. INN azimexon). After IV administration of 200 mg on 5 consecutive days or oral administration of 300 mg on 7 consecutive days a significant increase in the percentage of active T lymphocytes was seen. After in vitro incubation of different concentrations of BM 12.531 with blood from healthy donors there was a significant increase in the percentage of active T lymphocytes. No clear influence of BM 12.531 on the lymphocyte transformation caused by various concentrations of PHA could demonstrated because of the scatter.No side effects attributable to treatment with BM 12.531 were found, so that BM 12.531 is a good candidate for clinical trials. 相似文献
62.
Ralph E. J. Boerner 《American journal of botany》1986,73(9):1249-1257
Patterns of mycorrhizal infection, seasonal foliar nutrient concentrations, nutrient allocation to shoots and rhizomes, and nutrient resorption were measured in relation to soil nutrient availability in two species of perennial forest herbs, Geranium maculatum L. and Polygonatum pubescens Pursh., in four forest stands in southern and central Ohio. The percentage of plants with V-A mycorrhizae and the proportion of root length colonized by VAM structures increased with decreasing nutrient availability in both species. Foliar N and P concentrations in plants from lower fertility sites were as high, or higher, than those in plants from higher fertility sites; as a result, tissue nutrient enrichment ratios (foliar concentration/soil available concentration) increased with decreasing fertility. Proportional resorption of N and P generally decreased with decreasing nutrient availability, a pattern inconsistent with those exhibited by woody plants in these forest stands. We hypothesize that the inverse relationship between nutrient uptake efficiency (via mycorrhizae) and nutrient use efficiency (resorption) exhibited by these forest understory herbs, but not by trees or herbs from high-light environments, may be related to low-light limitation of energy reserves in the forest understory. 相似文献
63.
Finding new therapies to assist in the treatment of cancer is a major challenge of clinical research. Small molecules that inhibit different molecular targets at the different levels of the MAPK pathway have been developed. Several MEK inhibitors have been examined in early-phase clinical trials and the current state of clinical results using these therapies is presented here. 相似文献
64.
Dora Boerner 《Protoplasma》1952,41(2):168-177
65.
Jing Xu Zhengfan Xu Jun-Ying Zhou Zhengping Zhuang Enhua Wang Julie Boerner Gen Sheng Wu 《The Journal of biological chemistry》2013,288(46):33263-33271
TNF-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in transformed and tumor cells but not in normal cells, making it a promising agent for cancer therapy. However, many cancer cells are resistant to TRAIL, and the underlying mechanisms are not fully understood. Here, we show that the regulation of the PP2A and Src interaction plays a critical role in TRAIL resistance. Specifically, we show that TRAIL treatment activates the tyrosine kinase Src, which subsequently phosphorylates caspase-8 at tyrosine 380, leading to the inhibition of caspase-8 activation. We also show that upon TRAIL treatment, Src, caspase-8, and PP2A/C (a catalytic subunit of the PP2A phosphatase) are redistributed into lipid rafts, a microdomain of the plasma membrane enriched with cholesterol, where PP2A dephosphorylates Src at tyrosine 418 and in turn inhibits caspase-8 phosphorylation. Furthermore, we find that TRAIL treatment causes PP2A/C degradation. These data suggest that the balance between Src-mediated caspase-8 phosphorylation and the inactivation of Src-mediated caspase-8 phosphorylation by PP2A determines the outcome of TRAIL treatment in breast cancer cells. Therefore, this work identifies a novel mechanism by which the interaction between PP2A and Src in the context of caspase-8 activation modulates TRAIL sensitivity in cancer cells. 相似文献
66.
Recent infectious disease outbreaks have resulted in renewed recognition of the importance of risk communication planning and execution to public health control strategies. Key to these efforts is public access to information that is understandable, reliable and meets their needs for informed decision-making on protective health behaviours. Learning from the trends in sources used in previous outbreaks will enable improvements in information access in future outbreaks. Two separate random-digit dialled telephone surveys were conducted in Alberta, Canada, to explore information sources used by the public, together with their perceived usefulness and credibility, during the 2003 Severe Acute Respiratory Syndrome (SARS) epidemic (n = 1209) and 2009–2010 H1N1 pandemic (n = 1206). Traditional mass media were the most used information sources in both surveys. Although use of the Internet increased from 25% during SARS to 56% during H1N1, overall use of social media was not as high as anticipated. Friends and relatives were commonly used as an information source, but were not deemed very useful or credible. Conversely, doctors and health professionals were considered credible, but not consulted as frequently. The use of five or more information sources increased by almost 60% between the SARS and H1N1 surveys. There was a shift to older, more educated and more affluent respondents between the surveys, most likely caused by a decrease in the use of landlines amongst younger Canadians. It was concluded that people are increasingly using multiple sources of health risk information, presumably in a complementary manner. Subsequently, although using online media is important, this should be used to augment rather than replace more traditional information channels. Efforts should be made to improve knowledge transfer to health care professionals and doctors and provide them with opportunities to be more accessible as information sources. Finally, the future use of telephone surveys needs to account for the changing demographics of the respondents accessed through such surveys. 相似文献
67.
Invasion of globally threatened ecosystems dominated by arbuscular mycorrhizal plants, such as the alkaline prairies and serpentine
barrens of eastern North America, by species of ectomycorrhizal (ECM) pine (Pinus) seriously threatens the persistence, conservation, and ongoing restoration of these rare plant communities. Using Maryland
serpentine barrens and an Ohio alkaline prairie complex as model systems, we tested the hypothesis that the invasiveness of
Virginia pine (Pinus virginiana L.) into such communities is regulated by the spatial pattern of ECM fungal inoculum in the soil. ECM colonization of pine
seedlings can occur by (1) hyphae growing from the roots of mature ECM pines colonizing nearby seedlings (contagion model),
(2) pine seedlings being infected after germinating in open areas where spores are concentrated in feces of animals that have
consumed sporocarps (centers of infection model), and (3) colonization from spores that are wind-dispersed across the landscape
(background model). To test these models of dispersal of ECM fungal inoculum into these barrens, we used autocorrelation and
spatially explicit mapping techniques (semivariance analysis and kriging) to characterize the distribution and abundance of
ECM inoculum in soil. Our results strongly suggest that ECM fungi most often disperse into open barrens by contagion, thereby
facilitating rapid pine colonization in an advancing front from mature pine forests bordering the barrens. Spatial patterns
consistent with the centers of infection model were present but less common. Thus, current management techniques that rely
on cutting and fire to reverse pine invasion may be ineffective because they do not kill or disrupt hyphal mats attached to
mature roots of neighboring pines. Management alternatives are discussed. 相似文献
68.
Michelle L. Demory Julie L. Boerner Robert Davidson William Faust Tsuyoshi Miyake Icksoo Lee Maik H��ttemann Robert Douglas Gabriel Haddad Sarah J. Parsons 《The Journal of biological chemistry》2009,284(52):36592-36604
Co-overexpression of the epidermal growth factor (EGF) receptor (EGFR) and c-Src frequently occurs in human tumors and is linked to enhanced tumor growth. In experimental systems this synergistic growth requires EGF-dependent association of c-Src with the EGFR and phosphorylation of Tyr-845 of the receptor by c-Src. A search for signaling mediators of Tyr(P)-845 revealed that mitochondrial cytochrome c oxidase subunit II (CoxII) binds EGFR in a Tyr(P)-845- and EGF-dependent manner. In cells this association involves translocation of EGFR to the mitochondria, but regulation of this process is ill-defined. The current study demonstrates that c-Src translocates to the mitochondria with similar kinetics as EGFR and that the catalytic activity of EGFR and c-Src as well as endocytosis and a mitochondrial localization signal are required for these events. CoxII can be phosphorylated by EGFR and c-Src, and EGF stimulation reduces Cox activity and cellular ATP, an event that is dependent in large part on EGFR localized to the mitochondria. These findings suggest EGFR plays a novel role in modulating mitochondrial function via its association with, and modification of CoxII. 相似文献
69.
Characterization of chemically and virally transformed variants of Madin-Darby canine kidney (MDCK) epithelial cells 总被引:3,自引:0,他引:3
Oncogenic derivatives of Madin-Darby canine kidney (MDCK) cells were isolated in the nude mouse, and nononcogenic anchorage-independent transformants were isolated in vitro following chemical mutagenesis in vitro. These transformed cell lines as well as a Moloney sarcoma virus (MSV) transformed line were characterized with respect to their serum and anchorage requirements, growth rates, final saturation densities, and sensitivities to contact inhibition. None of these in vitro growth characteristics were found to correlate with tumorigenicity in nude mice. One tumorigenic clone, MDCK-T1, was characterized with respect to serum-free growth requirements, cAMP production, and ornithine decarboxylase (ODC) activity. These cells exhibited a significant reduction in the PGE1 requirement for growth, they produced higher levels of cAMP, and they expressed a reduced level of ODC activity relative to the parental MDCK cells. These findings may reflect changes in growth control mechanisms which accompany kidney epithelial cell tumorigenesis and suggest that the study of transformed lines derived in this manner could lead to the identification of in vitro properties which are associated with malignancy. 相似文献
70.
Ralph E. J. Boerner 《Oecologia》1983,59(1):129-134
The nutrient dynamics of upland forest sites in the New Jersey Pine Barrens exposed to different fire intensities were determined. Nutrient concentrations and inventories in biomass, litter, humus, and standing dead wood were determined for an unburned site, two sites burned by severe wildfire and two sites burned by light prescribed burning. Humus nutrient levels were similar among sites despite differing fire histories. Amounts of calcium, magnesium, and potassium in biomass and in litter were lower in wildfire sites than in prescribed burn sites, all of which were lower than the control. Standing dead wood nutrient levels were much higher in the wildfire sites than in the other three sites. Output of nutrients to groudwater correlated poorly with the amounts of nutrients retained in humus or standing dead wood; however strong inverse correlations were found between nutrient output and nutrient storage in biomass or biomass plus litter and humus. These results emphasize the central role of nutrient immobilization in regrowing biomass in after fire on nutrient poor soils. 相似文献