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131.
Roh-Eul Yoo Seung Hong Choi Hye Rim Cho Bong-sik Jeon Eunbyul Kwon Eung-gyu Kim Juyoung Park Wan-Jae Myeong Jae-Kyung Won Yun-Sang Lee Ji-Hoon Kim Sun-Won Park Chul-Ho Sohn 《PloS one》2014,9(9)
Background
Accurate diagnosis of lymph node metastasis is crucial in treatment planning for cancer patients. Despite the use of various parameters, making correct diagnosis of a small metastatic or a hyperplastic benign node is still a challenge. In this study, we evaluated the feasibility of detecting lymph node metastasis using a new ultrasmall superparamagnetic iron oxide particle, PJY10, in a rabbit model.Methods
To make metastatic and benign lymph nodes, either VX2 carcinoma or fecal material suspension was inoculated into thighs of 56 rabbits three weeks or three days before magnetic resonance (MR) imaging, respectively. T2*-weighted 3T MR imaging was performed before and 24 hours after PJY10 injection (5.2 [n = 15], 7.8 [n = 17], and 10.4 [n = 24] mg Fe/kg). MR images were correlated with pathologic results to calculate sensitivity and specificity. Quantitative analysis of the signal intensity (SI) – number of voxels[low] (the fraction of the number of voxels with the normalized SI on the postcontrast image lower than that on the precontrast image) and mean SI ratio – was also performed for each lymph node.Results
Sensitivities were 100% at all three dosages, whereas specificity increased with increasing dosage (89% at 10.4 mg Fe/kg). The benign nodes had a significantly higher number of voxels[low] and a lower mean SI ratio than the metastatic nodes at the dosage of 10.4 mg Fe/kg (P<.001). Az values were 0.905 for the number of voxels[low] and 0.952 for the mean SI ratio. The number of voxels[low] (P = .019) and the mean SI ratio (P = .034) had significant correlations with the histopathologic area ratio of metastatic foci in the metastatic nodes at 10.4 mg Fe/kg.Conclusions
PJY10 enabled clear demonstration of lymph node metastasis with high sensitivity and specificity at its optimal dosage of 10.4 mg Fe/kg. 相似文献132.
133.
Changes in process performance and the nitrifying bacterial community associated with an increase of thiocyanate (SCN−) loading were investigated in a pre-denitrification process treating industrial wastewater. The increased SCN− loading led to the concentration of total nitrogen (TN) in the final effluent, but increasing the internal recycling ratio as an operation parameter from 2 to 5 resulted in a 21% increase in TN removal efficiency. In the aerobic reactor, we found that the Nitrosomonas europaea lineage was the predominant ammonia oxidizing bacteria (AOB) and the percentages of the AOB population within the total bacteria increased from about 4.0% to 17% with increased SCN− concentration. The increase of nitrite loading seemed to change the balance between Nitrospira and Nitrobacter, resulting in the high dominance of Nitrospira over Nitrobacter. Meanwhile, a Thiobacillus thioparus was suggested to be the main microorganism responsible for the SCN− biodegradation observed in the system. 相似文献
134.
A new colorimetric chiral sensor material consisting of three different functional sites such as chromophore (2,4-dinitrophenylazophenol dye), binding site (crown ether), and chiral barrier (3,3'-diphenyl-1,1'-binaphthyl group) was prepared and applied to the recognition of the two enantiomers of primary amino alcohols and amines. Among five primary amino alcohols and two primary amines tested, the two enantiomers of phenylalaninol show the highest difference in the absorption maximum wavelength (Δλ(max)=43.5 nm) and in the association constants (K(S)/K(R)=2.51) upon complexation with the colorimetric chiral sensor material and, consequently, the two enantiomers of phenylalaninol were clearly distinguished from each other by the color difference. 相似文献
135.
Impaired interleukin-3 (IL-3) response of the A/J mouse is caused by a branch point deletion in the IL-3 receptor alpha subunit gene. 总被引:2,自引:0,他引:2 下载免费PDF全文
Interleukin-3 (IL-3) alone does not support hematopoietic colony formation of bone marrow cells from the A/J mouse. To elucidate the molecular lesion in A/J mice, we examined expression of the alpha and beta subunits of the IL-3 receptor (IL-3R). While IL-3R beta was normally expressed, IL-3R alpha was not detectable on the surface of A/J-derived cells by antibody staining. Genetic linkage analysis using recombinant inbred mouse strains between A/J and IL-3-responsive C57BL/6 indicated that the IL-3R alpha gene locus was responsible for the impaired IL-3 response in A/J mice. Molecular cloning and characterization of A/J-derived IL-3R alpha cDNA revealed that it lacked the sequence corresponding to exon 8, which encodes 10 amino acid residues in the extracellular domain. The aberrant splicing was due to a 5 base pair deletion at the branch point in intron 7 and was reproduced in heterologous cells by transfecting with an IL-3R alpha minigene carrying the deleterious intron. The A/J-specific abnormal form of IL-3R alpha was localized inside the cells, but not on the cell surface, providing the molecular basis for the impaired IL-3 response in the A/J mouse. 相似文献
136.
137.
McAllister SE Ashrafpour H Cahoon N Huang N Moses MA Neligan PC Forrest CR Lipa JE Pang CY 《American journal of physiology. Regulatory, integrative and comparative physiology》2008,295(2):R681-R689
We tested our hypothesis that postischemic conditioning (PostC) is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mitochondrial permeability transition pore (mPTP). In bilateral 8x13 cm pig latissimus dorsi muscle flaps subjected to 4 h ischemia, muscle infarction increased from 22+/-4 to 41+/-1% between 2 and 24 h reperfusion and remained unchanged at 48 (38+/-6%) and 72 (40+/-1%) h reperfusion (P<0.05; n=4 pigs). PostC induced by four cycles of 30-s reperfusion/reocclusion at the onset of reperfusion after 4 h ischemia reduced muscle infarction from 44+/-2 to 22+/-2% at 48 h reperfusion. This infarct protective effect of PostC was mimicked by intravenous injection of the mPTP opening inhibitor cyclosporin A or NIM-811 (10 mg/kg) at 5 min before the end of 4 h ischemia and was abolished by intravenous injection of the mPTP opener atractyloside (10 mg/kg) at 5 min before PostC (P<0.05; n=4-5 pigs). PostC or intravenous cyclosporin A injection at 5 min before reperfusion caused a decrease in muscle myeloperoxidase activity and mitochondrial free Ca2+ concentration and an increase in muscle ATP content after 4 h ischemia and 2 h reperfusion compared with the time-matched controls. These effects of PostC were abolished by intravenous injection of atractyloside at 5 min before PostC (P<0.05; n=6 pigs). These observations support our hypothesis that PostC is effective in salvage of ischemic skeletal muscle from reperfusion injury and the mechanism involves inhibition of opening of the mPTP. 相似文献
138.
Randell T. Libby Katharine A. Hagerman Victor V. Pineda Rachel Lau Diane H. Cho Sandy L. Baccam Michelle M. Axford John D. Cleary James M. Moore Bryce L. Sopher Stephen J. Tapscott Galina N. Filippova Christopher E. Pearson Albert R. La Spada 《PLoS genetics》2008,4(11)
At least 25 inherited disorders in humans result from microsatellite repeat expansion. Dramatic variation in repeat instability occurs at different disease loci and between different tissues; however, cis-elements and trans-factors regulating the instability process remain undefined. Genomic fragments from the human spinocerebellar ataxia type 7 (SCA7) locus, containing a highly unstable CAG tract, were previously introduced into mice to localize cis-acting “instability elements,” and revealed that genomic context is required for repeat instability. The critical instability-inducing region contained binding sites for CTCF—a regulatory factor implicated in genomic imprinting, chromatin remodeling, and DNA conformation change. To evaluate the role of CTCF in repeat instability, we derived transgenic mice carrying SCA7 genomic fragments with CTCF binding-site mutations. We found that CTCF binding-site mutation promotes triplet repeat instability both in the germ line and in somatic tissues, and that CpG methylation of CTCF binding sites can further destabilize triplet repeat expansions. As CTCF binding sites are associated with a number of highly unstable repeat loci, our findings suggest a novel basis for demarcation and regulation of mutational hot spots and implicate CTCF in the modulation of genetic repeat instability. 相似文献
139.
Nayoung Kim Soo‐Heon Park Geom Seog Seo Sang Woo Lee Jae Woo Kim Kwang Jae Lee Won‐Chang Shin Tae Nyeun Kim Moo‐In Park Jong‐Jae Park Su Jin Hong Ki‐Nam Shim Sang Wook Kim Yong‐Woon Shin Young‐Woon Chang Hoon Jai Chun Ok‐Jae Lee Won‐Joong Jeon Chan‐Guk Park Chang‐Min Cho Cheol Hee Park Sun Young Won Gin Hyug Lee Kyung Sik Park Jeong Eun Shin Heung Up Kim Joon Yong Park Hiun Suk Chae Geun Am Song Jae Gyu Kim Byung Chul Yoon Sangyong Seol Hyun Chae Jung In‐Sik Chung 《Helicobacter》2008,13(6):542-549
Background and Aims: Lafutidine is a novel H2‐receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7‐ or 14‐day lafutidine–clarithromycin–amoxicillin therapy versus a lansoprazole‐based regimen for Helicobacter pylori eradication. Methods: Four hundred and sixty‐three patients with H. pylori‐infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared. Results: The eradication rates by the intention‐to‐treat and per‐protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention‐to‐treat and per‐protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups. Conclusion: The results of this study showed that lafutidine–clarithromycin–amoxicillin therapy was a safe and effective as lansoprazole‐based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option. 相似文献
140.
Methanolic extracts of seven herbs (Acorus calamus, Acorus gramineus, Bupleurm facaltum, Dioscorea batatas, Epimedium koreanum, Poria cocos and Zizyphi jujuba) used in traditional Korean medicine for improvement of memory and cognition in old age were tested for cholinesterase inhibitory properties using the Ellman colorimetric method. Significant inhibition of the enzyme at 200 microg/ml was observed for extracts from A. calamus and E. koreanum. The possible bases for the reputation of these and the other herbs tested are discussed in the light of previous investigations into their chemistry and biological activity. 相似文献