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81.
82.
Y. Ohtsuki T. Yamaguchi H. Sonobe K. Takahashi K. Hayashi A. Takenaka H. Hashimoto K. Kuwabara T. Miyamoto N. Terao 《Biotechnic & histochemistry》1989,64(2):55-59
A new simplified method has been devised for staining aluminum and has been tested in paraffin sections of bone from 60 patients who have undergone hemodialysis. Iliac crest bone fragments were fixed in 20% phosphate-buffered formalin for less than a day and demineralized at room temperature in 10% phosphate-buffered formalin containing 5% formic acid for only 2 to 3 hr. Four-micron paraffin sections, accompanied by positive controls, were stained with Maloney's aluminum stain, the Berlin blue reaction for iron, dylon or Congo red for amyloid and von Kossa's reaction for calcium. Aluminum and iron were demonstrated particularly at the mineralizing front of bony tissues; aluminum in 52 cases, iron in 45. Dylon staining also gave positive results in 52 cases. It is important in determining whether aluminum deposition is present that the von Kossa reaction remains positive even after demineralization. This method may be more useful for demonstrating aluminum in bony tissues than the complicated and time-consuming resin-embedding method currently used. 相似文献
83.
84.
Hisashi Miyazaki Masatoshi Iida Yoshimasa Matsunaga Toshihiko Fujii Keiko Nambu Hideki Amejima Yoshinori Oh-e Hideo Furukawa Yukiharu Matsui Yasunobu Sohmura Masahisa Hashimoto 《Biotherapy》1989,1(1-2):47-57
The mode of antitumor action of rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation with respect to time course, dose-response relationships and selectivity of the effects. The maximal cytotoxic effect on tumor cells revealed by inhibition of DNA synthesis and maximal lesional effect on tumor vasculature revealed by change in blood pool-size in the tissue were detected at 30 min and I h after administration of rHu-TNF, respectively. The dose-response relationship between cytotoxic and tumoricidal effects of rHu-TNF was irrespective of administration route. ED50s of these antitumor effects afteri.v. administration of rHu-TNF were about 50 times as high as ED50s afteri.t. administration. ED50 ofi.t. given rHu-TNF for vascular effect was about 20 times as high as that for cytotoxicity while ED50 ofi.v. rHu-TNF for vascular effect was only 2–3 times as high as that for cytotoxicity. The whole body autoradiographies with [125I] HSA giveni.v. to see the blood influx into tumor tissue and [14C]thymidine given i.v. to see DNA synthesis in the whole body after administration of rHu-TNF revealed that the distribution of radioactivity was markedly changed in the tumor alone without any detectable change in other whole body tissues.In conclusion, thein vivo antitumor effect of rHu-TNF giveni.t. ori.v., appears to be exerted through the direct action on Meth A sarcoma rather than indirectly on tumor vasculature. Under present conditions, the effect of rHu-TNF in the whole body tissues seems rather selective on cells and vasculature of the tumor. 相似文献
85.
K Zenita K Hirashima K Shigeta N Hiraiwa A Takada K Hashimoto E Fujimoto K Yago R Kannagi 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(11):4442-4451
The expression of the VH genes in 46 murine hybridoma cells that secrete mAb directed to the cancer-associated carbohydrate Ag, especially acidic glycolipids such as gangliosides and sulfated glycoplipids, was analyzed by Northern hybridization of poly(A)+ RNA of hybridoma with cDNA probes for nine VH gene families. Different hybridomas tended to express VH genes of the same family when the cognate Ag had the same or similar carbohydrate structures; i.e., the VH genes of the J558 family (group 1) were preferentially expressed in the mAb directed to various gangliosides that have NeuAc alpha (or NeuGc alpha) 2-3 and/or 2-8 linkage (71%), the most common linkage of sialic acid residues in the gangliosides of higher animals, and the hybridomas directed to sulfated glycolipids also expressed mainly the VH genes of the J558 family (80%). In contrast, the five mAb directed to various gangliosides with NeuAc alpha 2-6 linkage were exclusively encoded by the VH genes of Q52 family (group 2, 100%), and three antibodies directed to gangliosides with a NeuAc alpha 2-9 linkage all expressed genes of J606 family (group 6, 100%). The VH family usage was largely correlated with the linkage of sialic acid residues in the cognate carbohydrate Ag, but was not correlated at all with the difference in the fine specificities toward the core neutral carbohydrate chain, to which the sialic acid residues were attached. These findings suggest that the VH gene family in these anticarbohydrate antibodies is selected, depending primarily on the linkage of the sialic acid residues in carbohydrate Ag; these residues form the immunodominant sugar residue in the respective antigenic determinant. 相似文献
86.
N Usuda H J Ma T Hanai S Yokota T Hashimoto T Nagata 《The journal of histochemistry and cytochemistry》1990,38(5):617-623
We report on the immunohistochemical demonstration of an enzyme at the electron microscopic level using specimens processed by rapid freezing and the freeze-substitution technique without the use of any chemical fixatives. Fresh rat liver tissue blocks were rapidly frozen by the metal contact method using liquid nitrogen, and were freeze-substituted with acetone without any chemical fixatives at -80 degrees C. Some of the freeze-substituted tissues were embedded in Lowicryl K4M at -20 degrees C; the others were returned to room temperature and embedded in Epok 812 at 60 degrees C. Ultra-thin sections were stained using anti-peroxisomal catalase antibody by the protein A-gold technique. The ultrastructure of the hepatocytes was very well preserved compared with that of conventionally processed tissues. The labeling for catalase was confined to peroxisomes. When the labeling density was compared among freeze-substituted tissues and conventionally processed tissues, that of freeze-substituted and Lowicryl K4M-embedded tissues was the most intense. These results show the usefulness of freeze-substituted tissues for immunohistochemical analysis of cell organelles. 相似文献
87.
K Tamura M Kobayashi Y Ishii T Tamura K Hashimoto S Nakamura M Niwa J Zapf 《The Journal of biological chemistry》1989,264(10):5616-5621
Rat insulin-like growth factor-I (IGF-I), a serum polypeptide with growth promoting activity, was isolated from rat serum by a combination of acid/ethanol extraction, affinity chromatography, and a series of reversed phase high performance liquid chromatography, cation exchange, and reversed phase. All peptide fragments produced by chymotrypsin digestion of reduced and carboxymethylated rat IGF-I were amino acid sequenced and compared with the sequence of human IGF-I. Three out of 70 of the rat amino acid residues differed from those of human IGF-I as follows: Asp20----Pro, Ser35----Ile and Ala67----Thr. Purified rat IGF-I cross-reacted with polyclonal anti-human IGF-I antibody 75% as compared to human IGF-I, but it cross-reacted only 3% with monoclonal anti-human IGF-I antibody. Thus, it is possible to monitor the metabolic fate of human IGF-I, when injected into rats, without interference by endogenous rat IGF-I. Rat IGF-I showed 65% activity in the radioreceptor, 28.6% activity in the lipogenesis and 22.5% activity in the free fatty acid release inhibition assays as compared to human IGF-I on a protein quantity basis. 相似文献
88.
At the developmental stage at which the apical hook passed the 3rd and 4th nodes, dark-grown seedlings of pea ( Pisum sativum L. cv. Progress No.9) opened the hook upright and then formed a new hook above the node nearly in the opposite direction to the previous one. In cv. Alaska, in contrast, many (about 84%) seedlings closed the hook in the original direction after they partially (up to about 110°) opened it at the 3rd node, thus doing a wagging movement, while a small percentage (about 16%) of the seedlings reversed the hook direction. Exposure to red light of cv. Alaska seedlings for 10 min increased the percentage of the hook reversion up to 71% or more. The hook reversion was never observed except when the hook part passed the nodes, suggesting the involvement of the nodes in the phenomenon. 相似文献
89.
90.
H Sohma H Hashimoto H Ohguro T Akino 《Biochemical and biophysical research communications》1992,184(1):175-182
When a mixture of bovine brain G-proteins (Gi/o) was loaded onto an octyl sepharose column in the presence of AlF4-, alpha-subunits of molecular weights 39 kDa and the 41 kDa were eluted separately, followed by the appearance of two distinct peaks containing beta gamma-subunits (beta gamma-I, beta gamma-II). Both beta gamma-I and beta gamma-II possessed identical beta-subunits but different gamma-subunits. The molecular weights of the two gamma-subunits determined by SDS-polyacrylamide gel electrophoresis both in the presence and absence of urea were 4.5 kDa (gamma-I) and 5.0 kDa (gamma-II). Tests indicated that the two isolated gamma-subunits are intact and have not undergone proteolysis. The amino acid composition of gamma-I appeared to be distinct from that of gamma-II. Therefore, this method is a simple procedure for isolating beta gamma-I and beta gamma-II. 相似文献