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71.
Chen PJ Liu Y Weiss TM Huang HW Sinn H Alp EE Alatas A Said A Chen SH 《Biophysical chemistry》2003,105(2-3):721-741
We summarize a series of experimental results made with the newly developed high resolution X-ray scattering (IXS) instrument on two pure lipid bilayers, including dimyristoylphosphatidylcholine (DMPC) and dilauroylphosphatidylcholine (DLPC) in both gel and liquid crystal phases, and lipid bilayers containing cholesterol. By analyzing the IXS data based on the generalized three effective eigenmode model (GTEE), we obtain dispersion relations of the high frequency density oscillations (phonons) of lipid molecules in these bilayers. We then compare the dispersion relations of pure lipid bilayers of different chain lengths among themselves and the dispersion relations of pure lipid bilayers with those of the cholesterol containing bilayers. We also compare our experimental results with collective dynamics data generated by computer molecular dynamics (MD) simulations for dipalmitoylphosphatidylcholine (DPPC) in gel phase and DMPC in liquid crystal phase. 相似文献
72.
Large species differences have been previously observed in the pharmacology of bradykinin (BK) B2 receptor antagonists. We investigated the effect of two novel non-peptide antagonists, compound 9 (a benzodiazepine peptidomimetic related to icatibant) and the thiosemicarbazide bradyzide on the rabbit B2 receptor (contractility of the jugular vein, competition of [3H]BK binding to a B2 receptor-green fluorescent protein (B2R-GFP) conjugate, subcellular distribution of B2R-GFP). While compound 9 is about 9000-fold less potent than icatibant, it shares with the latter peptide drug a selective, insurmountable and largely irreversible antagonist behavior against BK and the capacity to translocate B2R-GFP from the membrane into the cells. Bradyzide, reportedly very potent at rodent B2 receptors, was a competitive and reversible antagonist of moderate potency at the rabbit B2 receptor (contractility pA2 6.84, binding competition IC50 5 nM). The C-terminal region of icatibant, reproduced by compound 9, is likely to be important in the non-equilibrium behavior of icatibant. Bradyzide, a non-peptide antagonist developed on different structural grounds, is competitive at the rabbit B2 receptor. 相似文献
73.
Ying Jin Melanie L. McEwen M. Said Ghandour Joe E. Springer 《Cellular and molecular neurobiology》2001,21(2):123-172
Abstract List
Abstracts of XVth ASN National Meeting 相似文献74.
Transferrin receptor 2-alpha supports cell growth both in iron-chelated cultured cells and in vivo 总被引:11,自引:0,他引:11
Kawabata H Germain RS Vuong PT Nakamaki T Said JW Koeffler HP 《The Journal of biological chemistry》2000,275(22):16618-16625
In most cells, transferrin receptor (TfR1)-mediated endocytosis is a major pathway for cellular iron uptake. We recently cloned the human transferrin receptor 2 (TfR2) gene, which encodes a second receptor for transferrin (Kawabata, H., Yang, R., Hirama, T., Vuong, P. T., Kawano, S., Gombart, A. F., and Koeffler, H. P. (1999) J. Biol. Chem. 274, 20826-20832). In the present study, the regulation of TfR2 expression and function was investigated. A select Chinese hamster ovary (CHO)-TRVb cell line that does not express either TfR1 or TfR2 was stably transfected with either TfR1 or TfR2-alpha cDNA. TfR2-alpha-expressing cells had considerably lower affinity for holotransferrin when compared with TfR1-expressing CHO cells. Interestingly, in contrast to TfR1, expression of TfR2 mRNA in K562 cells was not up-regulated by desferrioxamine (DFO), a cell membrane-permeable iron chelator. In MG63 cells, expression of TfR2 mRNA was regulated in the cell cycle with the highest expression in late G(1) phase and no expression in G(0)/G(1). DFO reduced cell proliferation and DNA synthesis of CHO-TRVb control cells, whereas it had little effect on TfR2-alpha-expressing CHO cells when measured by clonogenic and cell cycle analysis. In addition, CHO cells that express TfR2-alpha developed into tumors in nude mice whereas CHO control cells did not. In conclusion, TfR2 expression may be regulated by the cell cycle rather than cellular iron status and may support cell growth both in vitro and in vivo. 相似文献
75.
p21WAF1/CIP1 Is Upregulated by the Geranylgeranyltransferase I Inhibitor GGTI-298 through a Transforming Growth Factor β- and Sp1-Responsive Element: Involvement of the Small GTPase RhoA
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76.
The structure of breast tissue is complicated and highly variable and presents a great challenge in the development of physical models that may be used to obtain its effective complex permittivity. Empirical models are commonly used by researchers to fit measured data and extrapolated to higher frequencies. However, these models have not been verified experimentally at higher frequencies. Theoretical models of tissue permittivity to explain the role of water are not available today. This communication is a systematic study of several models to estimate the complex permittivity of breast fat tissue based on volume content and distribution of water in the tissue. These models are implemented in (i) long wavelength, sparse concentration limit; (ii) full wave finite element simulation; and (iii) numerical implementation of dynamic multiple scattering theory. A comparison of the proposed models with experimental data is done at 3.2 GHz. Some of the measurement values are in fair agreement with the modeling. The results of the present study are useful for interpreting the large variability in experimentally measured values of the permittivity of breast fat tissue by taking the distribution of water into account. Bioelectromagnetics 30:669–677, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
77.
Abd El-Aziz A. Said Adriane G. Ludwick Heshmat A. Aglan 《Bioresource technology》2009,100(7):2219-2222
Raw bagasse or sugar cane cellulosic residues were modified using acylation grafting with fatty acid. The capability of the grafted bagasse to absorb oil from aqueous solution was studied and compared with the raw bagasse. It was found that the grafted material was significantly more hydrophobic than the raw bagasse. This grafted bagasse had little affinity for water and good affinity for oil. It was also found that bleaching of raw bagasse did not enhance its oil absorptivity. The grafted raw bagasse would be most suitable for applications where oil is to be removed from an aqueous environment. For oil absorbing applications in the absence of water, the raw bagasse was an excellent material. 相似文献
78.
79.
Agricola Joachim Charlotta Nilsson Said Aboud Muhammad Bakari Eligius F. Lyamuya Merlin L. Robb Mary A. Marovich Patricia Earl Bernard Moss Christina Ochsenbauer Britta Wahren Fred Mhalu Eric Sandstr?m Gunnel Biberfeld Guido Ferrari Victoria R. Polonis 《PloS one》2015,10(4)
Vaccine-induced HIV antibodies were evaluated in serum samples collected from healthy Tanzanian volunteers participating in a phase I/II placebo-controlled double blind trial using multi-clade, multigene HIV-DNA priming and recombinant modified vaccinia Ankara (HIV-MVA) virus boosting (HIVIS03). The HIV-DNA vaccine contained plasmids expressing HIV-1 gp160 subtypes A, B, C, Rev B, Gag A, B and RTmut B, and the recombinant HIV-MVA boost expressed CRF01_AE HIV-1 Env subtype E and Gag-Pol subtype A. While no neutralizing antibodies were detected using pseudoviruses in the TZM-bl cell assay, this prime-boost vaccination induced neutralizing antibodies in 83% of HIVIS03 vaccinees when a peripheral blood mononuclear cell (PBMC) assay using luciferase reporter-infectious molecular clones (LucR-IMC) was employed. The serum neutralizing activity was significantly (but not completely) reduced upon depletion of natural killer (NK) cells from PBMC (p=0.006), indicating a role for antibody-mediated Fcγ-receptor function. High levels of antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies against CRF01_AE and/or subtype B were subsequently demonstrated in 97% of the sera of vaccinees. The magnitude of ADCC-mediating antibodies against CM235 CRF01_AE IMC-infected cells correlated with neutralizing antibodies against CM235 in the IMC/PBMC assay. In conclusion, HIV-DNA priming, followed by two HIV-MVA boosts elicited potent ADCC responses in a high proportion of Tanzanian vaccinees. Our findings highlight the potential of HIV-DNA prime HIV-MVA boost vaccines for induction of functional antibody responses and suggest this vaccine regimen and ADCC studies as potentially important new avenues in HIV vaccine development.
Trial Registration
Controlled-Trials ISRCTN90053831 The Pan African Clinical Trials Registry ATMR2009040001075080 (currently PACTR2009040001075080) 相似文献80.
Abdelghani?GhazdaliEmail author Abdelilah?Hakim Amine?Laghrib Nezha?Mamouni Said?Raghay 《Theoretical biology & medical modelling》2015,12(1):25