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21.
Anti-idiotypic antibodies against UV-induced tumor-specific CTL clones. Preparation in syngeneic combination 总被引:2,自引:0,他引:2
K Kuribayashi C Tanaka Y Matsubayashi T Masuda H Udono M Abe E Nakayama H Shiku 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(11):4074-4080
In this study, we first established several CTL clones of (BALB/c x C57BL/6)F1 origin that were specific for either syngeneic UV female 1 or UV male 1 fibrosarcoma cell lines. All the CTL clones had Thy-1+ Lyt-2+ L3T4- phenotypes and showed Kd restriction when lysing the corresponding target cells. Sera obtained from syngeneic animals immunized with three CTL clones, 10B-5 for UV female 1, and CTL9 and CTL10 for UV male 1, showed specific inhibition of target cell lysis with the corresponding CTL clones. The inhibitory activities were found in sera of the majority of immunized animals. Because the inhibitory activity resides in protein A-binding fraction, mAb were produced by hybridizing spleen cells of hyperimmune animals. N1-56 was thus obtained from a mouse immunized with 10B-5 CTL clone reactive with UV female 1. N1-56 was clonotype specific, reacting with 10B-5 but not with other CTL lines or leukemia cell lines. No N1-56+ cells were detectable in thymocytes, lymph node cells, or spleen cells of either naive or UV female 1-immune CB6F1 mice. Immunoprecipitation showed that N1-56 reacts with 90,000 Mr molecules on 10B-5 CTL clone under nonreducing conditions and 45,000 Mr molecules under reducing conditions, indicating its reactivities with idiotypic determinants of TCR on the CTL clone. N1-56 inhibited lytic activity of 10B-5, but neither N1-56 nor alpha-10B-5 hyperimmune serum inhibited that of alpha-UV female 1 mixed lymphocyte tumor cell culture cells. N1-56 induced proliferation of 10B-5 without addition of Ag. 相似文献
22.
T Masuda F Tezuka H Konno A Togashi Y Itoh T Sugawara 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1988,10(4):294-298
Imprint preparations were used in addition to frozen sections in the intraoperative diagnosis of 37 cases of benign and malignant lesions of the thyroid gland, including adenomatous goiter, follicular adenoma, follicular carcinoma and papillary carcinoma. In the imprints, the cytologic features specific for carcinoma, as compared with benign lesions, were (1) the folding of the nuclear contour, (2) the increased density of the cytoplasmic matrix and (3) the frequent appearance of cell clusters of larger size. The size and frequency of cell clusters were morphometrically analyzed by a computer image analyzer. There was an increasing number of large clusters, plus the appearance of clusters of more than 300 micron in diameter, in both follicular and papillary carcinoma. In benign lesions, on the contrary, the majority of cells were isolated or in small clusters, the diameter of which never exceeded 300 micron in diameter. These results demonstrate that (1) the imprint cytology of the thyroid gland is useful in making a rapid intraoperative diagnosis and (2) the introduction of computer-assisted quantitative analysis is of practical value in the diagnosis of malignancy. 相似文献
23.
Matuo Y Nishi N Muguruma Y Yoshitake Y Masuda Y Nishikawa K Wada F 《Cytotechnology》1988,1(4):309-318
Among several detergents, a zwitterionic detergent, 3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate (CHAPS), was found to be least cytotoxic for cultured mammalian cells. CHAPS improved the activity recovery and elution profile of crude and purified fibroblast growth factors (FGFs) during chromatographies. Diluted preparations of FGFs were stabilized by CHAPS against the loss during storage. Amino acid sequence analysis was not disturbed by CHAPS. CHAPS was removable by reversed-phase high-performance liquid chromatography. These results indicate that CHAPS is useful as a non-cytotoxic stabilizing agent in purification of various kinds of bioactive polypeptides.Abbreviations -MEM
Alpha Modification of Eagle's Minimal essential medium
- CHAPS
3-[(3-cholamidopropyl)dimethylammonio]-1-propane sulfonate
- CHAPSO
3-[(3-cholamidopropyl)dimethylammonio]-2-hydroxy-1-propane sulfonate
- CS
Calf Serum
- EGF
Epidermal Growth Factor
- FGF
Fibroblast Growth Factor
- HPLC
High-Performance Liquid Chromatography
- NGF
Nerve Growth Factor
- NOG
1-O-n-octyl--D-glucopyranoside
- NP-40
Nonidet P-40
- PBS
Phosphate-Buffered Saline
- SB 12
3-(dodecylmethylammonio)-1-propane sulfonate
- SDS
Sodium Dodecyl Sulfate
- TGF- and
Transforming Growth Factor type and 相似文献
24.
The role of interstitial collagens in cleft formation of mouse embryonic submandibular gland during initial branching 总被引:8,自引:0,他引:8
Y Fukuda Y Masuda J Kishi Y Hashimoto T Hayakawa H Nogawa Y Nakanishi 《Development (Cambridge, England)》1988,103(2):259-267
An interstitial collagenase was purified from the explant medium of bovine dental pulp and was shown to degrade collagens I and III but not IV and V. The enzyme halted cleft initiation in the epithelium of 12-day mouse embryonic submandibular glands in vitro, indicating the active involvement of interstitial collagens in the branching morphogenesis. Transmission electron microscopic observation of the intact 12-day gland without any clefts showed the scattered localization of a few collagen fibrils at the epithelial-mesenchymal interface of the bulb and also revealed the presence of numerous microfibrils around the stalk. Collagen bundles were regularly seen close to the wavy basal lamina at the bottom of clefts of the intact 13-day gland and 12-day gland cultured for 17 h under normal conditions. Mesenchymal cells were found in the clefts together with the frequent localization of peripheral nerve fibres and capillary endothelial cells. The collagen bundles were more often observed in the 12-day gland cultured in the presence of bovine dental pulp collagenase inhibitor, which had been shown to enhance cleft formation. In contrast, collagen fibrils were rarely found at the epithelial-mesenchymal interface of the 12-day gland cultured in the presence of Clostridial or bovine dental pulp collagenase. The findings indicated that the formation of interstitial collagen bundles is essential to form clefts in the epithelium both in vivo and in vitro. 相似文献
25.
Takayuki Ohgushi 《Population Ecology》1988,30(1):57-68
The relationships between egg predation of an herbivorous lady beetle Epilachna niponica (Lewis ) and its predator, the earwig Anechura harmandi (Burr ), were examined in both time and space. In spite of little annual, changes in egg densities, egg mortality due to predation varied considerably. There was no, clear relationship between the earwig density and the proportionate predation over the five years. The seasonal occurrence of earwig nymphs on thistle plants, however, was closely synchronized with that of egg predation. Predator attacks on the beetle occurred in a time-restricted manner. Thus, later cohorts mostly escape from heavy predatory pressure. No spatially density-depent egg predation was detected at the level of either thistle plants or thistle patches. Furthermore, there was no indication of aggregative behaviour of the earwig in response to local egg density. The earwig density was more likely to be associated with particular localities with sandy deposits available for its nest site. 相似文献
26.
Yoshiaki Sumiyoshi Masahiko Kikuchi Morishige Takeshita Kohiti Ohshima Yuhiti Masuda 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(1):201-207
In Japan, histiocytic necrotizing lymphadenitis (Kikuchi’s disease) is a relatively common reactive lesion affecting lymph
nodes, but the histogenesis and pathogenesis of the disease have not been clarified. Alpha-interferon has a role in the body’s
defense against, viral infections. Using a polyclonal antibody to human alpha-interferon, we found numerous cells, mainly
histiocytes, containing alpha-interferon in affected foci in the lymph nodes from 24 patients with Kikuchi’s disease. Tubuloreticular
structures, thought by some authors to be associated with the production of interferon, were detected by electron microscopy
in histiocytes, activated lymphocytes and vascular endothelial cells in the affected foci. These results suggested that the
formation of tubuloreticular structures is a secondary phenomenon following stimulation by alpha-interferon. Further, the
activity of 2′–5′ oligoadenylate synthetase, which is induced by alpha-interferon and enhanced during the early or active
stage of viral infection, showed increased levels of activity in the active stage of Kikuchi’s disease and decreased to normal
levels in the convalescent stage 2 weeks later. These results suggested the possibility of a viral etiology for Kikuchi’s
disease. 相似文献
27.
Complete nucleotide sequence of the mitochondrial DNA from a liverwort,Marchantia polymorpha 总被引:1,自引:1,他引:0
Kenji Oda Katsuyuki Yamato Eiji Ohta Yasukazu Nakamura Miho Takemura Naoko Nozato Kinya Akashi Takeshi Kanegae Yutaka Ogura Takayuki Kohchi Kanji Ohyama 《Plant Molecular Biology Reporter》1992,10(2):105-163
Libraries of cosmid and plasmid clones covering the entire region of mtDNA from the liverwortMarchantia polymorpha were constructed. These clones were used for the determination of the complete nucleotide sequence of the liverwort mtDNA
totally 186,608 bp (GenBank no. M68929) and including genes for 3 species of ribosomal RNAs, 29 genes for 27 species of transfer
RNAs, and 30 genes for functionally known proteins (16 ribosomal proteins, 3 subunits of cytochromec oxidase, apocytochromeb protein, 3 subunits of H+-ATPase, and 7 subunits of NADH ubiquinone oxidoreductase). The genome also contains 32 unidentified open reading frames.
Thus the complete nucleotide sequences from both chloroplast and mitochondrial genomes have been determined in the same organism.
Plasmid clones are available upon the request.
Gene names are represented according to Lonsdale and Leaver (1988) with modifications recommended by Lonsdale (personal communication). 相似文献
28.
Kenji Kato Su-wan Oh Hiroyuki Yamamoto Takayuki Hanazato Ikuko Yasuda Akira Otuki Masayuki Takahashi 《Ecological Research》1992,7(3):267-276
In order to understand the control mechanisms of a large, stable bacterial standing stock, enclosure experiments were conducted
in a eutrophic lake, where both bacterial productivity and grazing pressure were very high. Total bacterial number in the
different enclosures ranged from 1.2 to 2.7×107 cells mL−1 throughout the experiment. The average bacterial cell production rate estimated from a grazer eliminating experiment was
6.3×105 cells mL−1 h−1. Difference in the bacterial cell production rate between shaded and unshaded enclosures was not apparent. Bacteria showed
a reduction in standing stock of only about 25–30% even after the supply of light was cut to 1%. Bacteria in the shaded enclosures
then recovered their production rate in the first 12 days of perturbation. Grazing pressure in the shaded enclosures was not
less than that for the control. Thus, it was considered a control mechanism of bacterial stable standing stock that the bacteria
shifted their organic substrate from extracellular dissolved organic carbon freshly released from phytoplankton to that already
stocked in the water column, though it is not known whether the dominant bacteria were the same. 相似文献
29.
Multiple rpoD-related genes of cyanobacteria. 总被引:3,自引:0,他引:3
Genomes of many eubacterial strains have been shown to encode for multiple rpoD-related genes. In this report, we describe the identification of the multiple rpoD-related genes of cyanobacterial strains. DNAs of three cyanobacterial strains, Anabaena sp. PCC7120, Synechococcus sp. PCC7942, and Synechocystis sp. PCC6803, were examined by Southern hybridization, using a synthetic probe designed for detecting rpoD or rpoD-related genes. Four or five hybridization signals were found in each DNA. Four DNA regions of Synechococcus sp. PCC7942 corresponding to the hybridization signals were cloned and partially sequenced. The sequence data indicate the presence of genes, named rpoD1, rpoD2, rpoD3, and rpoD4, whose products are highly similar to the basic structure of the principal sigma factors of eubacterial strains. The rpoD1 gene showed the greatest similarity to the sigA gene of Anabaena sp. PCC7120. 相似文献
30.
Takayuki Hoson Seiichiro Kamisaka Yoshio Masuda Masamichi Yamashita 《Journal of plant research》1992,105(1):53-70
We developed a three-dimensional (3-D) clinostat to simulate a microgravity environment and studied the changes in plant growth processes under this condition. The rate of germination of cress (Lepidium sativum), maize (Zea mays), rice (Oryza sativa), pea (Pisum sativum), or azuki bean (Vigna angularis) was not affected on the clinostat. The clinostat rotation did not influence the growth rate of their roots or shoots, except for a slight promotion of growth in azuki roots and epicotyls. On the contrary, the direction of growth of plant organs clearly changed on the 3-D clinostat. On the surface of the earth, roots grow downward while shoots upward in parallel to the gravity vector. On the 3-D clinostat, roots of cress elongated along the direction of the tip of root primordia after having changed the direction continuously. Rice roots also grew parallel to the direction of the tip of root primordia. On the other hand, roots of maize, pea, and azuki bean grew in a random fashion. The direction of growth of shoots was more controlled even on the 3-D clinostat. In a front view of embryos, shoots grew mostly along the direction of the tip of primordia. In a side view, rice coleoptiles showed an adaxial (toward the caryopsis) while coleoptiles of maize and epicotyls of pea and azuki bean an abaxial curvature. The curvature of shoots became larger with their growth. Such an autotropism may have an important role in regulation of life cycle of higher plants under a microgravity environment. 相似文献