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2.
Circulating tumor cells (CTCs), shed from primary tumors and disseminated into peripheral blood, are playing a major role in metastasis. Even after isolation of CTCs from blood, the target cells are mixed with a population of other cell types. Here, we propose a new method for analyses of cell mixture at the single-cell level using a microfluidic device that contains arrayed electroactive microwells. Dielectrophoretic (DEP) force, induced by the electrodes patterned on the bottom surface of the microwells, allows efficient trapping and stable positioning of single cells for high-throughput biochemical analyses. We demonstrated that various on-chip analyses including immunostaining, viability/apoptosis assay and fluorescent in situ hybridization (FISH) at the single-cell level could be conducted just by applying specific reagents for each assay. Our simple method should greatly help discrimination and analysis of rare cancer cells among a population of blood cells. 相似文献
3.
4.
Abstract Biovar A strains of Fusobacterium necrophorum exhibited high hydrophobicity when examined by the method of Rosenberg et al. Biovar B strains showed a lower cell surface hydrophobicity than biovar A strains. Biovar B strains were divided into 2 groups according to their hydrophobic activity. The strains of biovar A and the first group of biovar B were increasingly removed from aqueous phase to octane phase by increasing the volume of octane, but the turbidity of the second group of biovar B was not significantly affected. The hydrophobicity of biovar A strains decreased on heating at 60 and 100°C for 30 min. 相似文献
5.
Oka Kotaro; Ikeshima Hiroko; Ishikawa Hideo; Ohta Eiji; Sakata Makoto 《Plant & cell physiology》1988,29(5):771-775
We showed that the surface charge density of protoplasts canbe estimated by the 9-aminoacridine method. The estimated surfacecharge density of the protoplasts isolated from elongating regionsof Vigna mungo root was 39 ? 8 mC/m2. The negative surfacecharge density increased when protoplasts were treated withglutaraldehyde or when EDTA was added to the protoplast suspensionmedium. These results support the validity of our estimationof the surface charge density of protoplasts by the 9-aminoacridinemethod. The concentration of amino groups at the surface ofthe protoplasts was estimated to be 34 mC/m2. (Received June 19, 1987; Accepted April 11, 1988) 相似文献
6.
Summary A 0.7 kb DNA fragment of the Escherichia coli K12 chromosome was shown to contain the structural gene for RNAse III (rnc). The DNA sequence of the gene was determined and its alteration in an RNAse III defective mutant, AB301-105, was identified. DNA sequence analysis also showed that a secondary-site suppressor of a temperature-sensitive mutation in the E. coli ribosomal protein gene, rpsL, occurred within the rnc gene, providing genetic evidence for the interaction of ribosomal proteins with RNAse III, which in turn acts on the nascent ribosomal RNA during assembly of ribosomes in E. coli. 相似文献
7.
Hiroko Nashimoto Akiko Miura Haruo Saito Hisao Uchida 《Molecular & general genetics : MGG》1985,199(3):381-387
Summary Temperature-sensitive (ts) mutations were isolated within a ribosomal protein gene (rpsL) of Escherichia coli K12. Mutations were mapped by complementation using various transducing phages and plasmids carrying the rpsL gene, having either a normal or a defective promoter for the rpsL operon. One of these mutations, ts118, resulted in a mutant S12 protein which behaved differently from the wild-type S12 on CM-cellulose column chromatography. Suppressors of these ts mutations were isolated and characterized; one was found to be a mutation of a nonribosomal protein gene which was closely linked to the RNAase III gene on the E. coli chromosome. This suppressor, which was recessive to its wild-type allele, was cloned into a transducing phage and mapped finely. A series of cold-sensitive mutations, affecting the assembly of ribosomes at 20°C, was isolated within the purL to nadB region of the E. coli chromosome and one group, named rbaA, mapped at the same locus as the suppressor mutation, showing close linkage to the RNAase III gene. 相似文献
8.
The heterogeneity of human fibroblasts as determined from the effects of hydrocortisone on cell growth and specific dexamethasone binding 总被引:1,自引:0,他引:1
To elucidate the heterogeneity of human fibroblasts from lung and skin, the effects of hydrocortisone on cell proliferation and the specific dexamethasone binding to cells were studied. Hydrocortisone at physiological concentrations stimulated the proliferation in three strains of human fetal lung fibroblasts and inhibited it in two strains. There are two kinds of fibroblasts in the human fetal lung in addition to the human skin fibroblasts reported previously. Dexamethasone-binding experiments showed that human fibroblasts may be classified into two groups with respect to the dissociation constant (Kd) of the binding reaction. The heterogeneity of human fibroblasts shown by Kd could not be correlated to classification on the basis of the effects of hydrocortisone on cell proliferation. The differences in Kd for the binding reactions suggest differences in donor tissues from which human fibroblasts are derived. 相似文献
9.
Takashi Momoi Tatsuko Furuya Yoshiyuki Suzuki Hiroko Sato Nubuo Yamaguchi 《Bioscience reports》1985,5(3):267-273
The permanent human cell lines preserving defects of lysosomal enzymes, GM1-1019-SV and SA-1077-SV, were established from the respective fibroblasts from patients with GMl-gangliosidosis and Sandhoff disease by transfection with replication origin-minus simian virus 40 DNA. These ceils grow rapidly without entering senescence during more than 120 population doublings. The activity of -galactosidase in GM1-1019-SV and of B-N-acetylhexosaminidase in SA-1077-SV was respectively 40- and 180-fold lower than that of normal fibroblasts. 相似文献
10.
A structural locus (C-6) for the sixth component of complement in mice is assigned to chromosome 15. Three-point linkage analysis indicated that the order of loci is C-6, Gpt-1, Gdc-1, and that the map distances are 25.9±4.9 between C-6 and Gpt-1, and 36.4±5.5 between C-6 and Gdc-1. Since Gdc-1 is more distal than Gpt-1, and C-6 is 26 cM away from Gpt-1, it is estimated that the C-6 is proximal to the centromere. In addition, a new C6 form found in AKR mice is described. We propose the designation C6B for it and C-6
b
for the allele encoding C6B.Abbreviations used in this paper IEF
isoelectric focusing
- GPT
glutamic-pyruvic transaminase
- GDC
L-glycerol 3-phosphate dehydrogenase
- cM
centimorgan 相似文献