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81.
Teruo Okasora Mitsumasa Nagase Hiroshi Kawachi Katsuyuki Matsui Michiaki Orikasa Tetsuo Morioka Ichiroh Yamazaki Takashi Oite Fujio Shimizu 《Virchows Archiv. B, Cell pathology including molecular pathology》1991,60(1):41-46
Change in the localization of the antigen recognized by the proteinuria-inducing monoclonal antibody (MA) 5-1-6 in experimental nephrosis was studied by indirect and biotin-avidin immunofluorescence, and immunoperoxidase at light and electron microscopical levels. The proteinuric state was induced by the administration of the aminonucleoside of puromycin (PAN) or adriamycin. The antigen decreased in quantity and/or its distribution changed with an increase in the amount of protein excreted in both experimental models. Recovery from the alterations observed during the development and proteinuria appeared to occur when PAN-induced proteinuria subsided. This antigenic molecule may thus be essential for maintaining the normal permselectivity of glomerular capillary walls. 相似文献
82.
Michael I. Lerman Farida Latif Gladys M. Glenn Lambert N. Daniel Hiltrud Brauch Shigeto Hosoe Krista Hampsch John Delisio Mary Lou Orcutt O. Wesley McBride Karl-Heinz Grzeschik Takashi Takahashi John Minna Patrick Anglard W. Marston Linehan Berton Zbar 《Human genetics》1991,86(6):567-577
Summary A collection of 2,000 lambda phage-carrying human single-copy inserts (> 700 bp) were isolated from two chromosome-3 flow-sorted libraries. The single-copy DNA fragments were first sorted into 3p and 3q locations and about 700 3p fragments were regionally mapped using a deletion mapping panel comprised of two humanhamster and two-human-mouse cell hybrids, each containing a chromosome 3 with different deletions in the short arm. The hybrids were extensively mapped with a set of standard 3p markers physically localized or ordered by linkage. The deletion mapping panel divided the short arm into five distinct subregions (A-E). The 3p fragments were distributed on 3p regions as follows: region A, 26%; B, 31%; C, 4%; D, 4% and E, 35%. We screened 300 single-copy DNA fragments from the distal part of 3p (regions A and B) with ten restriction endonucleases for their ability to detect restriction fragment length polymorphisms (RFLPs). Of these fragments 110 (36%) were found to detect useful RFLPs: 35% detected polymorphisms with frequency of heterozygosity of 40% or higher, and 25% with frequency of 30% or higher. All polymorphisms originated from single loci and most of them were of the base pair substitution type. These RFLP markers make it possible to construct a fine linkage map that will span the distal part of chromosome 3p and encompasses the von Hippel-Lindau disease locus. The large number of single-copy fragments (2,000) spaced every 100–150 kb on chromosome 3 will make a significant contribution to mapping and sequencing the entire chromosome 3. The 300 conserved chromosome 3 probes will increase the existing knowledge of man-mouse homologies. 相似文献
83.
Sensitive detection of viral antigens with a new method, "laser magnet immunoassay". 总被引:1,自引:0,他引:1
H Mizutani M Suzuki H Mizutani K Fujiwara S Shibata K Arishima M Hoshino H Ushijima H Honma T Kitamura 《Microbiology and immunology》1991,35(9):717-727
A new method, "laser magnet immunoassay" (LMIA), has been developed for sensitive detection of viral antigens. Target viruses captured on microbeads were made to react with antibodies labeled with magnetite particles. In a magnetic field, magnetically labeled antigens dispersed in water were attracted to and concentrated at one point on the surface, resulting in the lifting up of a small surface area. A laser beam which was incident on the point reflected, making an interference fringe. The intensity of the fringe indicates the amount of the magnetite conjugated with antigen. A very low concentration of antigens, such as 5 particles of influenza virus and 0.1 pg/ml of human immunodeficiency virus (HIV) p24 antigen in human serum, could be detected by this method. Application of this method to diagnoses of viral diseases in early stages is discussed. 相似文献
84.
A nonisotopic method for determination of the in vivo activities of tyrosine hydroxylase in the rat adrenal gland 总被引:2,自引:0,他引:2
Y Hayashi S Miwa K Lee K Koshimura A Kamel K Hamahata M Fujiwara 《Analytical biochemistry》1988,168(1):176-183
A rapid and reliable method for determination of in vivo activities of tyrosine hydroxylase in the rat adrenal gland is presented. This method involves determining the rate of accumulation of 3,4-dihydroxyphenylalanine (Dopa) in the adrenal gland after decarboxylase inhibition by NSD 1015, using HPLC with electrochemical detection after purification of the acid-deproteinized tissue extract with Bio-Rex 70 columns followed by alumina batch method. Purification of the sample with alumina adsorption alone, a method usually used for purification of catecholamines and Dopa, was ineffective: epinephrine and norepinephrine, which are present in high concentrations, interfered with an accurate determination of Dopa, and dopamine, which is retained strongly on the reverse-phase column, interfered with a rapid analysis. Purification with Sephadex G-10 columns followed by alumina adsorption was also ineffective. After purification with columns of weak cation-exchange resins such as Bio-Rex 70 or Amberlite CG-50 followed by alumina adsorption, most of the epinephrine and norepinephrine was removed and dopamine was eliminated. Thus a rapid and accurate determination of Dopa could be made. Of the two cation exchangers, Bio-Rex 70 was more effective. Accumulation of Dopa in the adrenal gland was linear up to 30 min after administration of NSD 1015 and a plateau was reached with doses over 10 mg/kg. Using this method, we investigated the effects of immobilization stress, reserpine, and hypoxia on in vivo activities of tyrosine hydroxylase in the adrenal gland. 相似文献
85.
R Takashi 《Biochemistry》1988,27(3):938-943
By peptide isolation and analysis, it has been shown that the dansyl fluorophore of dansylcadaverine [N-(5-aminopentyl)-5-(dimethylamino)naphthalene-1-sulfonamide] transfers to Gln-41 of actin from rabbit skeletal muscle when the reaction is catalyzed by guinea pig liver transglutaminase. As a function of time, the degree of labeling asymptotically approaches 1 mol of dansyl/l mol of actin. About 80-85% of the attached dansyl fluorophore was found at Gln-41. Such labeled G-actin polymerizes to the same extent as control actin, but the polymerization rate is greater and the critical concentration is less than for control actin. Complete polymerization is accompanied by a 1.5-2.0-fold increase in the emission intensity of the attached fluorophore. Labeled F-actin thus obtained activates myosin subfragment 1 (S-1) Mg2+-ATPase activity with the same Kapp, and to the same Vmax, as control actin; moreover, when such labeled F-actin is cross-linked to S-1 by 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide, the resulting superactivation of Mg2+-ATPase is the same as that attained with control actin. The attributes of this label thus make it an ideal reporter of events in the N-terminal 10-kilodalton region of actin, and a new topological point for proximity mapping. 相似文献
86.
A novel enzyme immunoassay (EIA) for thyrotropin-releasing hormone (TRH) was developed which used N-(4-diazophenyl)maleimide (DPM) as a new heterobifunctional agent capable of cross-linking TRH to mercaptosuccinyl bovine serum albumin and to beta-D-galactosidase. The resulting conjugates act as the immunogen producing anti-TRH serum in rabbits and the enzyme marker of TRH in the EIA, respectively. This EIA with a double-antibody technique was sensitive and reproducible in measuring TRH at concentrations as low as 50 pg per tube, and monospecific to the hormone showing no cross-reactivity with the hormone analogue L-pGlu-L-His-L-Pro and TRH constituents. Using this assay, the distribution of immunoreactive TRH in the brain was determined easily in rats. The use of DPM should provide a valuable new method for developing EIA hitherto possible for other peptide hormones containing neither a free carboxy nor a free amino group, using imidazole, phenolic, and indole group(s) of the amino acid as a reaction site. 相似文献
87.
Fractionation and Estimation of Particle-Attached and Unattached Bradyrhizobium japonicum Strains in Soils 总被引:2,自引:2,他引:0 下载免费PDF全文
Rhizobial cells attached or unattached to soil particles were estimated. Nonsterile soils into which antibiotic-resistant mutants of Bradyrhizobium japonicum had been introduced were fractionated by a centrifugation technique into two fractions: A, which contained mainly rhizobial cells attached to soil particles, and F, which contained mainly rhizobial cells unattached to them. Rhizobial counts decreased in both fractions during incubation of the soil at 30°C, with a concomitant decrease in the proportion of the count of fraction F to that of fraction A. Sonication of fraction A of the soil incubated for more than 3 weeks caused an increase in the rhizobial count. The ratio of the count of fraction A estimated by the plant infection method to that estimated by the dilution plate method increased after 5 days of soil incubation. More than 90% of the indigenous rhizobia in an agricultural field existed in fraction A. These results suggest that the majority of rhizobial cells are attached to soil particles. 相似文献
88.
Quantitation of the Myelin-Associated Glycoprotein in Human Nervous Tissue from Controls and Multiple Sclerosis Patients 总被引:3,自引:2,他引:1
David Johnson Shuzo Sato Richard H. Quarles Takashi Inuzuka Roscoe O. Brady Wallace W. Tourtellotte 《Journal of neurochemistry》1986,46(4):1086-1093
Myelin-associated glycoprotein (MAG) was measured by radioimmunoassay in the human CNS and peripheral nervous system (PNS). The level of MAG, expressed as ng/microgram of total protein, was approximately 20-fold higher in whole homogenates of cerebral white matter (4.7 +/- 0.60) than of peripheral nerve (0.12-0.28). MAG concentrations were only slightly higher in the isolated myelin fractions from these tissues: CNS myelin, 5.6 ng/microgram; PNS myelin, 0.37 ng/microgram. The levels of MAG were measured in nine plaques, periplaque regions, and areas of macroscopically normal-appearing white matter (NAWM) from six separate multiple sclerosis brains and compared with the levels of other myelin proteins in the same samples. MAG and other myelin proteins were reduced to very low levels in plaques. The levels of MAG and basic protein (BP) and the activity of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNP) in periplaque areas were significantly lower than those in control white matter, and MAG and BP levels were also significantly reduced in NAWM. In a periplaque region and NAWM from the most rapidly progressing case of multiple sclerosis examined, the MAG content was between 30 and 35% of the control level, whereas BP and PLP levels and CNP activity were between 50 and 85% of control values. The reduction of MAG content in periplaque regions from all nine multiple sclerosis plaques examined was significantly greater than the reductions of BP level and CNP activity. In NAWM samples, the mean reduction of MAG content was also greater than the reductions of BP level and CNP activity, but the difference was only statistically significant in comparison to CNP.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
89.
Protective effect of monoclonal antibodies on lethal mouse hepatitis virus infection in mice. 总被引:15,自引:12,他引:3 下载免费PDF全文
Neutralizing and nonneutralizing monoclonal antibodies to the peplomer glycoprotein and nucleocapsid protein of a mouse hepatitis virus (MHV), MHV-NuU, protected mice against lethal MHV-2 challenge. Histopathologically, livers of mice receiving protective antibodies showed some focal necrotic lesions with remarkable cellular infiltration instead of fulminant hepatitis caused by MHV-2. 相似文献
90.
Growth and Aspartate Kinase Activity in Wheat Cell Suspension Culture: Effects of Lysine Analogs and Aspartate-Derived Amino Acids 总被引:1,自引:0,他引:1
Yamada Yasuyuki; Kumpaisal Rosarin; Hashimoto Takashi; Sugimoto Yukihiro; Suzuki Akinori 《Plant & cell physiology》1986,27(4):607-617
The effects of lysine analogs and aspartate-derived amino acidson the growth of wheat cell suspension culture were studied.S-(2-Aminoethyl)-L-cysteine (AEC), -hydroxylysine (DHL) andtrans-lysene caused complete growth inhibition at 1.0 mM. Thegrowth inhibition of lysine analogs were, in the order of decreasingeffectiveness; AECDHL, trans-lysene>oxalysine, homolysineand lysyne. cis-Lysene and methyllysine were not inhibitoryeven at concentrations of 10 mM. Lysine effectively relievedgrowth inhibition induced by the lysine analogs. Lysine plusthreonine showed concerted inhibition, which was relieved bythe addition of methionine. Activity of aspartate kinase extracted from wheat cell suspensionculture was strongly inhibited by L-lysine; 0.75 to 1 mM oflysine was required for half-maximal inhibition. Threonine andmethionine, individually or in combination with lysine, showedno inhibitory effect on the enzyme activity. S-Adenosylmethionine,when added with lysine in equimolar concentrations, enhancedthe feedback inhibition by lysine, lowering the concentrationof lysine for half-maximal inhibition to 0.13 mM. The aspartatekinase isolated from the cells cultured in the presence of 5mM lysine did not differ in regulatory properties from the enzymefrom the cells cultured without lysine. AEC at 5 mM inhibitedthe enzyme activity by 50%. Other lysine analogs were not inhibitoryto the enzyme activity even at 10 mM. Growth inhibition of wheat suspension culture by aspartate-derivedamino acids and lysine analogs were discussed in relation totheir inhibitory effects on aspartate kinase activity. (Received October 25, 1985; Accepted February 26, 1986) 相似文献