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11.
Koichi Iijima 《Cell and tissue research》1970,103(4):460-474
Summary Detailed histochemical studies have been conducted on the morphology of the Golgi apparatus by applying the thiamine pyrophosphatase technique (Novikoff and Goldfisher, 1961) to the neurons of supraoptic and paraventricular nuclei of normal and dehydrated rabbits. The neurons in both nuclei were classified into five categories on the basis of the morphology of the Golgi apparatus. The number of cells in individual categories were counted to evaluate the percentage of each category in the whole nucleus.Neurons have many vesicles which show the tendency to form clusters. Such clusters are present also in the basal bodies. The Golgi apparatus is localized near one side of the nucleus in many neurons. The neurons indicate phasic activity of resting, anabolic and catabolic stages under normal conditions.During dehydration, the Golgi apparatus went through the three stages of network formation, the increase of the budding-off process and later on disintegration. The supraoptic nucleus reacted to the TPPase test more severely than the paraventricular nucleus, whereas the former went through the stages more slowly than the latter. The paraventricular nucleus also revealed sensitivity to osmotic stress. 相似文献
12.
Haruaki Uchiyama Koichi Ohara Kazuko Haga Tatsuya Haga Arata Ichiyama 《Journal of neurochemistry》1990,54(6):1870-1881
Muscarinic acetylcholine receptors purified from porcine cerebra or atria were covalently labeled with [3H]propylbenzilylcholine mustard ([3H]PrBCM), and then the labeled receptors were subjected to limited hydrolysis with trypsin, V8 protease, and lysyl endopeptidase, followed by analysis involving sodium dodecyl sulfate-polyacrylamide gel electrophoresis, fluorography, autoradiography, or immunostaining. The labeled peptides were located on the basis of their reactivity with antibodies raised against three synthetic peptides with partial sequences of the m1 or m2 receptor, and of their sensitivity to endoglycosidase F, which was taken as evidence that they contain glycosylation sites near the N terminus. The [3H]PrBCM-binding site in both cerebral and atrial receptors was found to be located between the N terminus and the second intracellular loop, because the size of the smallest deglycosylated peptide that contained both the [3H]PrBCM-binding and glycosylation sites was approximately 16 kDa. Cerebral receptors were 32P-phosphorylated with protein kinase C, and the major phosphorylation sites in cerebral muscarinic receptors were found to be located in a C-terminal segment including a part of the third intracellular loop, because a 32P-labeled peptide of 12-14 kDa reacted with anti-(m1 C-terminal peptide) antiserum. The presence of an intramolecular disulfide bond, probably between Cys 98 and Cys 178 in the first and second extracellular loops, respectively, was suggested by the finding that a peptide of approximately 17 kDa containing the [3H]PrBCM-binding site, but not the glycosylation sites, was partly converted to a peptide of approximately 12 kDa on treatment with beta-mercaptoethanol. 相似文献
13.
Koichi Rikimaru Hitomi Toda Noriko Tachikawa Nobuyuki Kamata Shoji Enomoto 《In vitro cellular & developmental biology. Plant》1990,26(9):849-856
Summary A novel protein-free synthetic medium has been developed for the culture of human squamous cell carcinoma cells. This medium,
designated PF86-1, supports the serial subcultivation of six out of nine human squamous cell carcinoma cell lines in a protein-free,
chemically defined condition without the adapting culture from serum-containing conditions. These cell lines growing in PF86-1
exhibited nearly equal potency to grow in massive culture without noticeable changes in morphology but presented a significantly
decreased level of colony forming efficiency when compared with the cells cultured in serum-containing media, suggesting the
implication of some autocrine mechanism. Interestingly, this medium supported the growth of normal human squamous cells of
oral mucosa and skin for more than 2 mo. in the primary explant culture in spite of high levels of calcium ion concentration,
where the overgrowth of fibroblasts as contaminant was not observed. These results suggest that PF86-1 supports the growth
of cells derived from epidermal tissues selectively and provides the same defined condition for growth of malignant and nonmalignant
human squamous cells. It seems, therefore, that PF86-1 allows investigations on the products of squamous cell carcinoma cells
or on the differences of growth mechanisms between normal and neoplastic human squamous cells. 相似文献
14.
Meenu Kapoor Tatsuya Wakasugi Koichi Yoshinaga Masahiro Sugiura 《Molecular & general genetics : MGG》1996,250(6):655-664
ThechiL gene product is involved in the light-independent synthesis of chlorophyll in photosynthetic bacteria, green algae and non-flowering plants. The chloroplast genome ofChlorella vulgaris strain C-27 contains the first example of a splitchiL gene, which is interrupted by a 951 bp group I intron in the coding region. In vitro synthesized pre-mRNA containing the entire intron and parts of the flanking exon sequences is able to efficiently self-splice in vitro in the presence of a divalent and a monovalent cation and GTP, to yield the ligated exons and other splicing intermediates characteristic of self-splicing group I introns. The 5 and 3 splice sites were confirmed by cDNA sequencing and the products of the splicing reaction were characterized by primer extension analysis. The absence of a significant ORF in the long P9 region (522 nt), separating the catalytic core from the 3 splice site, makes this intron different from the other known examples of group I introns. Guanosine-mediated attack at the 3 splice site and the presence of G-exchange reaction sites internal to the intron are some other properties demonstrated for the first time by an intron of a protein-coding plastid gene. 相似文献
15.
Comparison of OspA Serotypes for Borrelia burgdorferi Sensu Lato from Japan,Europe and North America
Toshiyuki Masuzawa Bettina Wilske Tetsuro Komikado Hiroyuki Suzuki Hiroki Kawabata Nanao Sato Koichi Muramatsu Nobutake Sato Emiko Isogai Hiroshi Isogai Russell C. Johnson Yasutake Yanagihara 《Microbiology and immunology》1996,40(8):539-545
Sixty-one Borrelia burgdorferi sensu lato strains from various sources (ticks, human, and wild animals) in Japan and two strains from ticks in Far Eastern Russia were classified on the basis of reactivity with 16 monoclonal antibodies (mAb) to outer surface protein A (OspA) and by DNA-DNA hybridization assay. Eleven OspA serotypes (J1 to J11) were recognized among the Japanese and the Far East Russian isolates (serotypes J1 to J9 were identified as B. garinii, serotype J10 was identified as B. afzelii, and serotype J11 corresponded to B. japonica), whereas 7 OspA serotypes for North American and European isolates previously reported (Bettina Wilske et al, J. Clin. Microbiol. 31:340-350, 1993) were not observed except for OspA serotype 2 which showed identical reactivity with OspA serotype J10. This finding provides helpful information for understanding the geographical distribution of Lyme disease borrelia and the development of vaccine and diagnostic tests. In conclusion: 1. B. burgdorferi sensu stricto has not been observed in Japan, 2. Japanese B. afzelii isolates are closely related to those from Europe, 3. B. garinii isolates from Japan are highly heterogeneous and apparently different from European B. garinii isolates. 相似文献
16.
Souhei Sugita Misako Namima Toshitaka Nabeshima Koichi Okamoto Hiroshi Furukawa Yasuhiro Watanabe 《Neurochemistry international》1996,28(5-6):545-550
For the purpose of studying a role of immediate early genes in psychotomimetic-induced behavioral excitation, we experimentally enhanced the locomotor activity of mice by acute administration of phencyclidine and examined the expression and localization of the c-Fos-like and c-Jun-like immunoreactivities in brain regions. A single injection of phencyclidine (5.0 mg/kg, i.p.) significantly increased not only the locomotor activity but also the expression of c-Fos-like immunoreactivity in several brain regions, particularly in the parietal cortex, hippocampal dentate gyrus, piriform cortex and hypothalamus. Interestingly, the c-Fos-like immunoreactivity in the parietal cortex continued to increase for 1 week after the phencyclidine injection. These results indicate that phencyclidine, even injected only once, can induce the persistent expression of c-Fos or c-Fos-related protein(s) in the mouse brain, and also suggest the possibility that such a c-Fos expression may underlie the behavioral and/or psychotomimetic effects of phencyclidine. 相似文献
17.
Koike Hiroyuki; Yoneyama Koichi; Kashino Yasuhiro; Satoh Kazuhiko 《Plant & cell physiology》1996,37(7):983-988
Interactions of externally added plastoquinone (PQ) derivatives(PQ0-PQ3) with the photosystem II (PSII) acceptor side wereinvestigated in PSII membrane fragments prepared from spinachby measuring the photoreduction rates of PQ derivatives at variousPQ concentrations, and the following results were obtained. From the kinetic analysis, all the PQ derivatives (PQ0-PQ3)except PQ3 were shown to accept electrons at two sites (theQB site and the PQ site) as in the case of Synechococcus vulcanusPSII particles with benzoquinone derivatives [Satoh et al. (1995)Plant Cell Physiol. 36: 597]. Affinities of PQ derivatives at the QB site increased as thelength of the isoprene side chain got longer, while those atthe PQ site were not very much different for all the PQ derivativestested in this study. The inhibitory effect of DCMU was noncompetitive, and, therefore,the affinity of PQ3 for the PQ site was determined while thatfor the QB site could not be estimated presumably due to itsfairly high affinity to the site. Based on the results obtained using PQ derivatives, the mechanismof interaction of an authentic PQ, PQ9, at the QB site is discussed. (Received May 2, 1996; Accepted July 24, 1996) 相似文献
18.
We examined the applicability of radiotelemetry to studies of acorn dispersal byApodemus mice and compared its efficiency with the of this spool-and-line method. Installation of a transmitter (2.2 g) onto acorns
did not interfere with the transporting and feeding behavior of the mice. We were able to detect all transmitter-installed
acorns and follow the daily changes in the sites in which they were hoarded, while we missed 59% of the spool-tied acorns
due to mice breaking the threads. Mice carried transmitter-installed acorns farther than spool-tied ones. The radiotelemetry
method is superior to the spool-and-line method and useful for the study of hoarding behavior in rodents. 相似文献
19.
Koichi Suzuki Misa Iwata Shigenori Ito Kiyoshi Matsui Atsuko Uchida Yasuhiko Mizoi 《Human genetics》1994,94(2):129-135
The “a” subunit of human coagulation factor XIII (F13A) exhibits genetic polymorphism defined by four common alleles, F13A*1A, *1B, *2A, and *2B. We have previously suggested on the basis of the isoelectric focusing patterns of the four allele products that point mutations at two separate sites and one intragenic crossing over might be involved in the genes of F13A polymorphism. Here, we report nucleotide substitutions associated with F13A polymorphism. A C/T transition of the second nucelotide of codon 564 in exon 12 is responsible for the difference between F13A*1A and *1B and that between F13A*2A and *2B, and a set of two base changes in codons 650 and 651 in exon 14 leads to the differences between F13A*1A and *2A and those between F13A*1B and *2B. The four combinations of the point mutations at the two exons thus correspond to the four alleles, two of which were generated by the point mutations from ancestral monomorphic gene. The results suggest strongly that intragenic crossing over must be involved in the genesis of the fourth allele. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods discriminating these base changes in exons 12 and 14 are also presented. 相似文献
20.