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61.
62.
Development of human pancreas 总被引:2,自引:0,他引:2
Masashi Fukayama Michio Ogawa Yukiko Hayashi Morio Koike 《Differentiation; research in biological diversity》1986,31(2):127-133
The developmental sequence of human pancreatic secretory proteins has not previously been studied in detail. We applied immunohistochemistry to study 20 fetal and neonatal pancreas' (8th to 39th gestational weeks) using antisera against the following pancreatic secretory proteins: pancreatic secretory trypsin inhibitor (PSTI), serine proteinases (trypsin, chymotrypsin, and elastase I), and amylase. PSTI was first detected in developing buds of the pancreas during the 8th gestational week, and proteinases were observed in acinar cells during the 14th week of gestation. Immunoreactivity for both PSTI and proteinases was found in most acinar cells soon after their appearance. Immunoreactivity for amylase could not be detected in fetal or neonatal pancreas tissue. PSTI was also found in developing islets during the 14th gestational week, but the number of immunoreactive cells had decreased by term. Cells positive for serine proteinases were occasionally in contact with islets in second-trimester fetuses. In discussing these results, we give particular attention to the nonparallel appearance of secretory products in the fetal pancreas, and the significance of cells immunoreactive for secretory proteins in endocrine islets. 相似文献
63.
Kazuo Ota Soji Kurita Kazumasa Yamada Tohru Masaoka Yoshiro Uzuka Nobuya Ogawa 《Cancer immunology, immunotherapy : CII》1986,23(1):5-10
Summary In a cooperative randomized control study of immunotherapy with bestatin in combination with chemotherapy in adults with acute nonlymphocytic leukemia (ANLL), 101 patients (48 in the bestatin group and 53 in the control group) out of 115 patients registered were evaluated as eligible. The bestatin group achieved a statistically significant prolongation of survival compared with the control group in overall ANLL and acute myelogenous leukemia. In the analysis of patient age, the bestatin group achieved a statistically significant prolongation of both the remission duration and survival in patients aged 50 to 65 years, while the differences were not significant in the 15 to 49 age group. The bestatin group tended to achieve a higher rate of reinduction of remission in patients who had recurrence of leukemia. Side effects developed in only 5 (9.6%) of 52 patients treated with bestatin. None of these side effects were particularly serious in nature. It is concluded that bestatin is useful for prolongation of survival of adult patients with ANLL, making for a longer remission duration especially in elderly patients and with few side effects. 相似文献
64.
Gastric K+-stimulated p-nitrophenylphosphatase cytochemistry 总被引:1,自引:0,他引:1
Summary A cytochemical study of gastric K+-stimulated p-nitrophenylphosphatase (K-NPPase) activity, corresponding to a K+-stimulated phosphoprotein phosphatase of H-K-ATPase system, has been made by a new cytochemical method.Sections of fixed guinea pig gastric mucosa in a mixture of 2% paraformaldehyde and 0.25% glutaraldehyde, were incubated with the incubation medium (1.0 M glycine-0.1 M KOH buffer, pH 9.0, 2.5 ml; 1.1 M KCl, 0.5 ml; 10 mM lead citrate dissolved in 50 mM KOH, 4 ml; levamisole, 6.0 mg; dimethyl sulfoxide, 2.0 ml; 0.1 M p-nitrophenylphosphate (Mg-salt), 1.0 ml; ouabain, 73.0 mg) for 30 min at room temperature. Under a light microscope the specific gastric K-NPPase reaction was distributed only in the parietal cells of the fundic glands. The electron microscopic cytochemistry showed that the gastric K-NPPase activity was localized on the membrane lining the apical surfaces, secretory canaliculi and tubulovesicles. On the other hand, ouabain-sensitive K-NPPase activity (Na-K-ATPase) was demonstrated to localize only in the basolateral membrane of parietal cells with Mayahara's method.These findings support the interrelationships between the apical surface membrane, secretory canalicular membrane and tubulovesicles, and the functional differentiation of the membrane between the secretory membrane and basolateral membrane.In honour of Prof. P. van DuijnPart of this paper was presented at the 24th Annual Meeting of the Japan Society of Histochemistry and Cytochemistry held in Nagoya, October 27–28, 1983 (Ogawa KS, Fujimoto K, Ogawa K (1983) A new lead citrate method for the cytochemical demonstration of the H+–K+-ATPase with p-NPP as a substrate. Acta Histochem Cytochem 16:662)This study was supported by Grants-in-Aid for Encouragement of Young Scientists No. 60770019 to K. Fujimoto from the Ministry of Education, Science and Culture, the Japanese Government 相似文献
65.
Isolation and characterization of a human interleukin 2 gene 总被引:1,自引:0,他引:1
S Mita S Maeda K Obaru N Nishino K Shimada T Hirano K Onoue T Ogawa H Ogawa 《Biochemical and biophysical research communications》1983,117(1):114-121
An interleukin 2 (IL-2) gene was isolated from a Charon 4A human gene library. Electron microscopic examination of 15 heteroduplexes formed between the genomic DNAs and the IL-2 cDNAs demonstrated that the size of the IL-2 gene is about 5.1 +/- 0.5 kb and that there are at least two introns in this gene. Nucleotide sequence of the 5' flanking region of the IL-2 gene showed a homology with that of the corresponding region of the human immune interferon gene. 相似文献
66.
Hirofumi Ogawa Yoshihisa Ishiguro Motoji Fujioka 《Archives of biochemistry and biophysics》1983,226(1):265-275
Guanidoacetate methyltransferase (EC 2.1.1.2) has been purified about 800-fold from rat liver. The purified preparation shows a single protein band on polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. The molecular weight of the enzyme is estimated to be 25,000 and 26,000 by Sephadex gel molecular-exclusion chromatography and by electrophoresis in polyacrylamide gradient gel, respectively. The sodium dodecyl sulfate-denatured enzyme also has a molecular weight of 26,000; thus, the enzyme is a monomeric protein. Guanidoacetate methyltransferase as isolated is catalytically inactive, but is readily reactivated by incubation with a thiol. The reactivated enzyme, which contains 3 mol of sulfhydryl groups/mol of enzyme, is again inactivated by oxidized glutathione. This inactivation is accompanied by the disappearance of two sulfhydryl residues. The relationship between the loss of enzyme activity and the number of residues disappeared indicates that the integrity of these sulfhydryl residues is critical for activity. The oxidized enzyme fails to bind the substrate S-adenosylmethionine as evidenced by the equilibrium dialysis study. Alkylation of the nonoxidizable sulfhydryl by N-ethylmaleimide shows that this residue is also essential for activity. UV absorption, fluorescence, and CD spectra show no difference between the reduced and oxidized enzymes, but the former is more susceptible to proteolytic attack by trypsin. The enzyme has an isoelectric pH of 5.3, and is most active at pH 9.0. From the CD spectrum, an α helix content of 15% is calculated. The Km values for guanidoacetate and S-adenosylmethionine are 97.5 and 6.73 μm, respectively, at pH 8.0 and 37 °C. 相似文献
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68.
69.
The effects of a synthetic growth promoter, 4-ethoxy-l-( p -tolyl)-S-triazine-2,6 (1H, 3H)-dione [TA], on growth and gravireaction of Zea mays L. (cv. LG 11) roots were investigated. In horizontal, intact roots, pretreatment with TA at 4 × 10−4 M inhibited the gravireaction. If the pretreated roots were rinsed with a buffer solution before incubation, the TA effect was reduced, indicating that a continuous presence of TA was necessary for its maximal activity. On the other hand, the TA pretreatment (1×10−5 , 1×10−4 and 4 × 10−4 M ) promoted the elongation of these roots. The TA effect was stronger for illuminated roots than for those kept in darkness. TA also decreased the lateral curvature of half-decapitated roots maintained vertically in light. This indicates that the action of TA could be associated with some growth inhibiting substances produced or released in cap cells. 相似文献
70.
Several investigators have described hemopoietic colonies expressing multilineage differentiation in culture. We recently identified a class of murine hemopoletic progenitors which form blast cell colonies with very high replating efficiencies. In order to clarify further the relationship between progenitors for blast cell colonies and progenitors for the multilineage hemopoietic colonies in culture, we carried out analyses of kinetic and differentiation properties of murine blast cell colonies. Serial observations of the development of blast cell colonies into multilineage (and single lineage) colonies in cultures of spleen cells obtained from 5-fluorouracil (5-FU)-treated mice confirmed the transitional nature of the murine blast cell colonies. The data also suggested that the early pluripotent progenitors are in G0 for variable periods, and that when triggered into cell cycle, they proliferate at relatively constant doubling rates during the early stages of differentiation. The notion that some of the pluripotent progenitors are in G0 was also supported by long-term thymidine suicide studies in which spleen cells were exposed to 3H-thymidine with high specific activity for 5 days in culture, washed, and assayed for surviving progenitors. Comparison of replating abilities of day-7 and day-16 blast cell colonies from normal as well as 5-FU-treated mice indicated that some of the day-7 blast cell colonies are derived from maturer populations of progenitors which are sensitive to 5-FU. In contrast, progenitors for the day-16 blast cell colonies are dormant in cell cycle and were not affected by 5-FU treatment. Previously we reported that progenitors for day-16 blast cell colonies have a significant capacity for self-renewal. These observations suggest the hypothesis that the capability for self-renewal is accompanied by long periods of G0, and that once commitment to differentiation takes place, then active cell division occurs. 相似文献