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81.
Ira R. Kim Kiichi Murakami Nien-Jung Chen Samuel D. Saibil Elzbieta Matysiak-Zablocki Alisha R. Elford Madeleine Bonnard Samuel Benchimol Andrea Jurisicova Wen-Chen Yeh Pamela S. Ohashi 《Apoptosis : an international journal on programmed cell death》2009,14(9):1039-1049
The p53-induced protein with a death domain, PIDD, was identified as a p53 target gene whose main role is to execute apoptosis
in a p53-dependent manner. To investigate the physiological role of PIDD in apoptosis, we generated PIDD-deficient mice. Here,
we report that, although PIDD expression is inducible upon DNA damage, PIDD-deficient mice undergo apoptosis normally not
only in response to DNA damage, but also in response to various p53-independent stress signals and to death receptor (DR)
engagement. This indicates that PIDD is not required for DNA damage-, stress-, and DR-induced apoptosis. Also, in the absence
of PIDD, both caspase-2 processing and activation occur in response to DNA damage. Our findings demonstrate that PIDD does
not play an essential role for all p53-mediated or p53-independent apoptotic pathways.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
82.
Biological invasions can have severe and widespread impacts on ecological communities. A few species of ants have become particularly
damaging invaders but quantitative data of their impacts on many taxa is still lacking. We provide experimental evidence using
artificial nests baited with quail eggs that the invasive Argentine ant (Linepithema humile) can be a significant avian nest predator – Argentine ants recruited to more nests and in higher abundance than the native
ant species they displace. However, at a site invaded by Argentine ants, we monitored over 400 nests of a ground-nesting species,
the Dark-eyed Junco (Junco hyemalis), and found that less than 2% of nests failed as a result of Argentine ant predation/infestation. A review of the literature
also suggests that Argentine ants may not be a serious threat to bird nests relative to other predators or parasites. However,
invasive ants with the capability of overwhelming prey though stinging (specifically the red-imported fire ant, Solenopsis invicta), may have a higher impact on avian nesting success.
Received 14 January 2005; revised 28 April 2005; accepted 12 May 2005. 相似文献
83.
Ahn JS Musacchio A Mapelli M Ni J Scinto L Stein R Kosik KS Yeh LA 《Journal of biomolecular screening》2004,9(2):122-131
A high-throughput assay for tau phosphorylation by cdk5/p25 is described. Full-length recombinant tau was used as a substrate in the presence of saturating adenosine triphosphate (ATP). Using PHF-1, an antibody directed specifically against 2 tau phosphorylation epitopes (serine 396 and serine 404), an enzyme-linked immunosorbent assay (ELISA)-based colorimetric assay was formatted in 384-well plates. The assay was validated by measuring kinetic parameters for cdk5/p25 catalysis and known inhibitors. Rate constants for the site-specific phosphorylations at the PHF-1 epitopes were determined and suggested preferential phosphorylation at these sites. The performance of this assay in a high-throughput format was demonstrated and used to identify inhibitors of tau phosphorylation at specific epitopes phosphorylated by cdk5/p25. 相似文献
84.
Wen-Chiuan Tsai Jong-Shiaw Jin Wei-Kuo Chang De-Chuan Chan Ming-Kung Yeh Shiou-Chih Cherng Li-Fan Lin Lai-Fa Sheu You-Chen Chao 《The journal of histochemistry and cytochemistry》2007,55(9):955-962
Cortactin and fascin-1 are important factors in tumor progression. We tested the hypothesis that cortactin and fascin-1 expression correlates with clinicopathological parameters of gastric adenocarcinoma. Immunohistochemical analysis of cortactin and fascin-1 was done using tissue microarrays of 100 surgical specimens, including 20 well-differentiated, 20 moderately differentiated, and 60 poorly differentiated gastric adenocarcinomas. Among the 20 well-differentiated gastric adenocarcinomas, 15 cases (75%) showed negative or weak staining (1+); 5 cases (25%) had moderate (2+) or strong (3+) cortactin expression. Among the 60 poorly differentiated gastric adenocarcinomas, more than three-quarters of the cases (76.7%) had moderate or strong cortactin expression; 14 cases (23.3%) had weak staining. Of 20 well-differentiated gastric adenocarcinoma cases, 14 (70%) showed negative or weak staining of fascin-1, whereas nearly one-third (30%) had moderate or strong expression. Among the 60 poorly differentiated gastric adenocarcinomas, 32 (53.3%) exhibited moderate or strong fascin-1 expression; fewer than half of the cases showed negative or weak staining. Higher intensity of cortactin and fascin-1 staining correlated directly with more-advanced cancer stages (TNM) and inversely with survival rates. Our findings suggest the possibility that pharmacological inhibitors of cortactin and fascin-1 activity may slow down tumor progression and prolong survival time in patients with gastric adenocarcinomas. 相似文献
85.
86.
Lin AY Chua MS Choi YL Yeh W Kim YH Azzi R Adams GA Sainani K van de Rijn M So SK Pollack JR 《PloS one》2011,6(2):e16636
Purpose
We sought to identify genes of clinical significance to predict survival and the risk for colorectal liver metastasis (CLM), the most common site of metastasis from colorectal cancer (CRC).Patients and Methods
We profiled gene expression in 31 specimens from primary CRC and 32 unmatched specimens of CLM, and performed Significance Analysis of Microarrays (SAM) to identify genes differentially expressed between these two groups. To characterize the clinical relevance of two highly-ranked differentially-expressed genes, we analyzed the expression of secreted phosphoprotein 1 (SPP1 or osteopontin) and lymphoid enhancer factor-1 (LEF1) by immunohistochemistry using a tissue microarray (TMA) representing an independent set of 154 patients with primary CRC.Results
Supervised analysis using SAM identified 963 genes with significantly higher expression in CLM compared to primary CRC, with a false discovery rate of <0.5%. TMA analysis showed SPP1 and LEF1 protein overexpression in 60% and 44% of CRC cases, respectively. Subsequent occurrence of CLM was significantly correlated with the overexpression of LEF1 (chi-square p = 0.042), but not SPP1 (p = 0.14). Kaplan Meier analysis revealed significantly worse survival in patients with overexpression of LEF1 (p<0.01), but not SPP1 (p = 0.11). Both univariate and multivariate analyses identified stage (p<0.0001) and LEF1 overexpression (p<0.05) as important prognostic markers, but not tumor grade or SPP1.Conclusion
Among genes differentially expressed between CLM and primary CRC, we demonstrate overexpression of LEF1 in primary CRC to be a prognostic factor for poor survival and increased risk for liver metastasis. 相似文献87.
88.
Interactions of aminopyridines with potassium channels of squid axon membranes. 总被引:26,自引:0,他引:26 下载免费PDF全文
The effects of aminopyridines on ionic conductances of the squid giant axon membrane were examined using voltage clamp and internal perfusion techniques. 4-Aminopyridine (4-AP) reduced potassium currents, but had no effect upon transient sodium currents. The block of potassium channels by 4-AP was substantially less with (a) strong depolarization to positive membrane potentials, (b) increasing the duration of a given depolarizing step, and (c) increasing the frequency of step depolarizations. Experiments with high external potassium concentrations revealed that the effect of 4-AP was independent of the direction of potassium ion movement. Both 3- and 2-aminopyridine were indistinguishable from 4-AP except in potency. It is concluded that aminopyrimidines may be used as tools to block the potassium conductance in excitable membranes, but only within certain specific voltage and frequency limits. 相似文献
89.
Zulfi Haneef Agatha Lenartowicz Hsiang J. Yeh Jerome Engel Jr. John M. Stern 《Journal of visualized experiments : JoVE》2014,(90)
Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE. 相似文献
90.
The regulator of G protein signaling (RGS) proteins are one of the essential modulators for the G protein system. Besides regulating G protein signaling by accelerating the GTPase activity of Gα subunits, RGS proteins are implicated in exerting other functions; they are also known to be involved in several diseases. Moreover, the existence of a single RGS protein in plants and its seven-transmembrane domain found in 2003 triggered efforts to unveil detailed structural and functional information of RGS proteins. We present a method for real-time examination of the protein-protein interactions between RGS and Gα subunits. AtRGS1 from plants and RGS4 from mammals were site-directedly labeled with the fluorescent probe Lucifer yellow on engineered cysteine residues and used to interact with different Gα subunits. The physical interactions can be revealed by monitoring the real-time fluorescence changes (8.6% fluorescence increase in mammals and 27.6% in plants); their correlations to functional exertion were shown with a GTPase accelerating activity assay and further confirmed by measurement of K(d). We validate the effectiveness of this method and suggest its application to the exploration of more RGS signaling partner proteins in physiological and pathological studies. 相似文献