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211.
212.
Development and evaluation of a protein microarray chip for diagnosis of hepatitis C virus 总被引:3,自引:0,他引:3
A protein chip diagnostic kit was developed for the diagnosis of hepatitis C virus (HCV) based on the protein chip technique and the immuno-concentration method. This kit was designed for low-density protein chips and also for the availability of multiple sample screening. Applicability of the chip was evaluated using 96 blood specimens and the results were compared to results of an anti-HCV enzyme immunoassay (EIA) test. With further development, the technology associated with the development of this chip could be applied to the simultaneous detection of multiple protein-protein, protein-ligand interactions. 相似文献
213.
Nonlinear 3-D models with fluid-structure interactions (FSI) based on in vitro experiments are introduced and solved by ADINA to perform flow and stress/strain analysis for stenotic arteries with lipid cores. Navier-Stokes equations are used as the governing equations for the fluid. Hyperelastic Mooney-Rivlin models are used for both the arteries and lipid cores. Our results indicate that critical plaque stress/strain conditions are affected considerably by stenosis severity, eccentricity, lipid pool size, shape and position, plaque cap thickness, axial stretch, pressure, and fluid-structure interactions, and may be used for possible plaque rupture predictions. 相似文献
214.
The cellular responses of Pseudomonas sp. HK-6 to explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) have been extensively analyzed in this study. The stress shock proteins, which might contribute to enhancing the cellular resistance to the cytotoxic effect of RDX, were induced at different concentrations of RDX used as a substrate for cell culture of Pseudomonas sp. HK-6. The proteins were identified as 70-kDa DnaK and 60-kDa GroEL by SDS-PAGE and Western blot using the anti-DnaK and anti-GroEL monoclonal antibodies. The stress shock proteins induced by RDX were found to increase in proportion to the RDX concentration used for this work. Analysis of membrane fatty acids of strain HK-6 following exposure to RDX showed that the amounts of dominant lipids 16:1 7c/15:0 iso 2OH, 16:0 and 18:1 7c/9t/12t decreased substantially or were not detected in the cells exposed to RDX, while amounts of lipids 10:0 iso, 14:1 5c/5t and 16:10 methyl increased dramatically. Scanning electron microcopy analyses revealed the presence of perforations and irregular rod shapes with wrinkled surfaces for cells treated with 0.135 mM RDX for 12 h, suggesting that RDX has a substantial cytotoxic impact on cells of strain HK-6. 相似文献
215.
216.
Kurukulasuriya R Sorensen BK Link JT Patel JR Jae HS Winn MX Rohde JR Grihalde ND Lin CW Ogiela CA Adler AL Collins CA 《Bioorganic & medicinal chemistry letters》2004,14(9):2047-2050
Biaryl amides derived from a reported series of ureas 1 were evaluated and found to be potent human glucagon receptor antagonists. The benzofuran analogue 6i was administered in Sprague-Dawley rats and blocked the effects of an exogenous glucagon challenge. 相似文献
217.
Jeong LS Kim MJ Kim HO Gao ZG Kim SK Jacobson KA Chun MW 《Bioorganic & medicinal chemistry letters》2004,14(19):4851-4854
On the basis of high binding affinity at the A(3) adenosine receptor of 3'-aminoadenosine derivatives with hydrogen bonding donor ability, novel 3'-ureidoadenosine analogues were synthesized from 1,2:5,6-di-O-isopropylidene-d-glucose in order to lead to stronger hydrogen bonding than the corresponding 3'-aminoadenosine derivatives. However, the synthesized 3'-ureidoadenosine analogues were totally devoid of binding affinity, because 3'-urea moiety caused steric and electrostatic repulsions at the binding site of the A(3) adenosine receptor, leading to conformational distortion. 相似文献
218.
Ataxia-telangiectasia, an evolving phenotype 总被引:10,自引:0,他引:10
Ataxia-telangiectasia (A-T) is a progressive neurodegenerative disorder, with onset in early childhood and a frequency of approximately 1 in 40,000 births in the United States. A-T is seen among all races and is most prominent among ethnic groups with a high frequency of consanguinity. The syndrome includes: progressive cerebellar ataxia, dysarthric speech, oculomotor apraxia, choreoathetosis and, later, oculocutaneous telangiectasia. Immunodeficiency with sinopulmonary infections, cancer susceptibility (usually lymphoid), and sensitivity to ionizing radiation are also characteristic. Laboratory findings include: (1) elevated alphafetoprotein (AFP), (2) cerebellar atrophy on magnetic resonance imaging, (3) reciprocal translocations between chromosomes 7 and 14 in lymphocytes, (4) absence or dysfunction of the ATM protein, (5) radiosensitivity, as demonstrated by colony survival assay (CSA), and (6) mutations in the ATM gene. The latter are usually truncating or splicing mutations; approximately 10% are missense mutations. Mutations are found across the entire gene. Almost all recurring mutations are found on unique haplotypes that represent founder effects and ancestral relationships between patients. In addition to radiosensitivity and sensitivity to radiomimetic chemicals, the phenotype of A-T cells includes defective damage-induced activation of the cell cycle checkpoints at G1, S and G2/M. With the aid of molecular testing, A-T can now be distinguished from other autosomal recessive cerebellar ataxias (ARCAs) such as Friedreich ataxia, Mre11 deficiency (AT-like disease), and the oculomotor apraxias 1 (aprataxin deficiency) and 2 (senataxin deficiency). Other "A-T variants" include: (1) Nijmegen breakage syndrome (NBS) or nibrin/Nbs1 deficiency, with microcephaly and mental retardation but without ataxia, apraxia, or telangiectasia, and 2) A-T(Fresno), a phenotype that combines features of both NBS and A-T, with mutations in the ATM gene. The term "A-T variant" has a diminishing usefulness. 相似文献
219.
Experimental study of rat beta islet cells cultured under simulated microgravity conditions 总被引:5,自引:0,他引:5
Song C Duan XQ Li X Han LO Xu P Song CF Jin LH 《Acta biochimica et biophysica Sinica》2004,36(1):47-50
To observe the effects of simulated microgravity on beta islet cell culture, we have compared the survival rates and the insulin levels of the isolated rat islet cells cultured at micro- and normal gravity conditions. The survival rates of the cells cultured were determined by acridine orange-propidium iodide double-staining on day 3, 7 and 14. The morphology of the cells was observed by electron microscopy. Insulin levels were measured by radio immuno assays. Our results show that the cell number cultured under the microgravity condition is significantly higher than that under the routine condition (P<0.01). Some tubular structure shown by transmission electron microscopy, possibly for the transport of nutrients, were formed intercellularly in the microgravity cultured group on day 7. There were also abundant secretion particles and mitochondria in the cytoplasm of the cells. Scanning electron microscopy showed that there were holes formed between each islet, possibly connecting with the nutrient trans 相似文献
220.
Wang W Ke S Wu Q Charnsangavej C Gurfinkel M Gelovani JG Abbruzzese JL Sevick-Muraca EM Li C 《Molecular imaging》2004,3(4):343-351
In vivo optical imaging is potentially useful for evaluating the presence of tumor markers that are targets of molecular medicine. Here we report the synthesis and characterization of integrin alphavbeta3-targeted peptide cyclo(Lys-Arg-Gly-Asp-Phe) [c(KRGDf )] labeled with fluorescence dyes with wavelength spanning from the visible/near infrared (Cy5.5) to the true near infrared (IRDye800) for optical imaging. In vitro, the peptide-dye conjugates bound specifically to tumor cells expressing alphavbeta3. When administered intravenously into mice at a dose of 6 nmol /mouse, the conjugates accumulated in tumors expressing alphavbeta3. The tumor-to-background ratios for human KS1767 Kaposi's sarcoma in mice injected with Cy5.5-c(KRGDf ) and Cy5.5 were 5.5 and 1.5, respectively. Preinjection of c(KRGDf ) blocked the uptake of Cy5.5-c(KRGDf ) in tumors by 89%. In alphavbeta3-positive M21 and alphavbeta3-negative M21-L human melanoma, fluorescence intensity in the tumor of mice injected with IRDye800 - c(KRGDf ) was 2.3 and 1.3 times that in normal tissue, respectively. Dynamic imaging revealed that Cy5.5- c(KRGDf ) was rapidly taken up by KS1767 tumor immediately after bolus injection. The rate of its uptake in the tumor was reduced by preinjection of c(KRGDf ) in an interval time-dependent manner. Our data suggest that near-infrared fluorescence imaging may be applied to the detection of tumors expressing integrin alphavbeta3 and to the assessment of the optimal biological dose and schedule of targeted therapies. 相似文献