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Volume 8 (1983)
- Issue 4 Pages 315-
- Issue 3 Pages 199-
- Issue 2 Pages 91-
- Issue 1 Pages 1-
Volume 8, Issue 1
Displaying 1-10 of 10 articles from this issue
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Shiro Matsuura, Rie Masuda, Osamu Sakai, Yutaka Tashiro1983 Volume 8 Issue 1 Pages 1-9
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSPrefixed nuclei were isolated from rat liver after perfusion with dilute glutaraldehyde. These nuclei sometimes were associated with the rough endoplasmic reticulum (ER), and occasionally continuity of the outer nuclear membrane with rough ER membrane was found. When these prefixed nuclei were incubated with ferritin antibody conjugates against cytochrome P-450, the cytoplasmic face of the outer nuclear membrane was labeled with ferritin similar to the labeling of the rough ER membrane. In the nuclear pore region, ferritin particles were present on the outer membrane up to the outer annuli of the pore complexes.
When unfixed nuclei were incubated at 0-4°C or at 20°C, some outer nuclear membranes were detached from the nuclear surface. In this case the nuclear pore complexes remained associated with the inner nuclear membrane, and small inside-out vesicles were formed at these pore regions. We also found some rough vesicles heavily labeled with ferritin particles within the nuclear matrix. They probably were derived from the rough ER or from the outer nuclear envelope which was internalized artificially during incubation.View full abstractDownload PDF (1447K) -
Hideki Gotoh, Toshifumi Takenaka, Masanori Shozushima1983 Volume 8 Issue 1 Pages 11-18
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSSkinned nerve fiber was prepared by treating a giant axon of squid with saponin. Filamentous networks and membranous organelles such as vacuoles, smooth membranes and mitochondria were present after the extraction. Ruthenium red staining of the extracted tissue showed dense fibrillar networks in the cytoplasm that correspond to the "microtrabeculae" or "cytoskeleton" reported by other investigators. Our method of preparation, thus, gives further evidence that these structures are not the result of artifactual condensation or precipitation. The present results also indicated that the networks are composed of acid mucopolysaccharides and/or mucoproteins. The density of microtubules was not changed by the extraction per se, but the number of microtubules remaining after extraction decreased by alteration of environmental conditions such as low temperature (4°C), or the presence of Ca++ (1 mM), Mg++ free medium or colchicine (1 mM). These conditions are known to inhibit axonal transport. The usefulness of our extracted cytoplasm as a model of microtubule-related physiological functions is discussed.View full abstractDownload PDF (798K) -
in Vitro: Their Alkaline Phosphatase ActivityHiro-aki Kodama, Hideki Koyama, Hiroko Sudo, Shiro Kasai1983 Volume 8 Issue 1 Pages 19-27
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSBy an in vitro colony assay and cytochemical staining, we investigated the capacity of mouse bone marrow fibroblasts to differentiate into adipocytes and to express alkaline phosphatase (ALP) activity. Gluco-corticoids enhanced colony formation of the fibroblasts, and stimulated their adipose conversion (55-65 % of the colonies became adipocyte-positive), but they did not affect ALP activity. The fibroblasts became heterogenous in size and morphology after growing in vitro then differentiated into adipocytes.
All the cell types had ALP activity, and more than 95 % of the colonies contained ALP-positive cells. ALP staining was strongest in cells in the early stage of adipose conversion, gradually decreasing with maturation. Our results indicate that the majority of the mouse bone marrow fibroblasts that formed colonies under our culture conditions are preadipocytes. We conclude that these fibroblasts originate from adventitial reticular cells present in bone marrow stroma because reticular cells have been reported to possess high ALP activity and have been suggested to differentiate into adipocytes.View full abstractDownload PDF (5356K) -
Ahmed Kabir, Makoto Watanabe, Zenju Takeda, Tomohiko Kizaki, Yoshinori ...1983 Volume 8 Issue 1 Pages 29-34
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSDistribution of peanut agglutinin binding sites was studied histologically with horseradish peroxidase labelled and fluorescein isothio-cyanate labelled peanut agglutinin in terms of cell differentiation in rat lymphatic organs, (thymus, spleen, lymph nodes).
In this study, alcohol-fixed paraffin-embedded tissue sections were used and proved to be useful for the histochemical study with peanut agglutinin.
In the germinal center of the lymph node, cells were weakly positive for peanut agglutinin binding sites but not in the mantle zone of the lymph follicle. In the thymus, the cortical thymocytes were weakly positive for peanut aggluti-nin binding sites but not in the medulla. In the spleen, some cells on the peri-phery of the white pulp were weakly positive for PNA binding sites but cells around the central artery were not positive. Large cells with granular cytoplasma around the sinus of the spleen and lymph node, thought to be fixed macrophages, were strongly positive for PNA binding sites.View full abstractDownload PDF (4259K) -
Kazuhiro Ishii, Tadashi Sudo, Michiaki Kohno, Motoi Oguchi, Kazukiyo O ...1983 Volume 8 Issue 1 Pages 35-42
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSLipid droplets appeared during the growing phase in the culture medium of incompletely transformed rat fibroblasts (HY1) induced by AccI-H fragments of adenovirus 12 DNA. These droplets consisted of neutral lipids, DNA, histones and RNA. Electron microscopic observations showed that the droplets had no lipid-bilayers on their surfaces which account-ed for the tendency of the droplets to readily fuse together and become larger, and that the inner structures of the droplets looked like networks of fibrous matter. Experiments with DNA hybridization showed that the droplet DNA was composed of both cellular and adenoviral DNA, and that the cellular DNA in the droplets seemed to be derived from various cell DNA sequences. These results suggest that the droplets were derived from parts of the nuclear components of HY1 cells. The mechanisms for droplet release are discussed.View full abstractDownload PDF (6381K) -
Miyako H. Takegami1983 Volume 8 Issue 1 Pages 43-55
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSThe cytological effects of nalidixic acid and novobiocin, inhibitors of DNA synthesis, on meiotic division in explanted microsporocytes of Lilium longiflorum were examined. Microsporocytes in the late G2 phase of premeiosis and in the early meiotic prophase were cultured in vitro for discrete periods in the presence of various concentrations of one of these inhibitors. The main effects of 0.4 mM nalidixic acid applied during leptonema and zygonema were suppression of meiotic development and the production of sticky chromosomes. At 0.1 to 0.2 mM, the meiotic rate was greatly reduced, and an application to cells in late G2 phase or early leptonema greatly affected chromosome pairing and chiasma formation, eventually giving rise to univalent or highly achiasmatic chromosomes.
Electron microscopy showed that nalidixic acid does not interfere with ongoing synapsis, but has its effect on chiasma formation by suppressing the initiation of formation of synaptinemal complexes. These results are evidence that this drug interferes with the mechanism of initiation of synapsis, but not with the maintenance of chromosome integrity. Similar results were obtained with microsporocytes exposed to novobiocin at concentrations of 0.005 to 0.02 mM. The significance of DNA synthesis during the zygotene stage is discussed on the basis of these observations.View full abstractDownload PDF (6391K) -
Hideko Urushihara, Yoji Ikawa1983 Volume 8 Issue 1 Pages 57-65
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSThe calcium-independent mechanism of cell adhesion was studied in normal and polyoma virus-transformed BHK cells. The degree of Ca2+-independent adhesion was greatly reduced in pyBHK cells, whereas Ca2+-dependent adhesion occurred to the same degree as in BHK cells. This decrease was shown not to be caused by simple masking of the adhesion sites or by their altered sensitivity to trypsin.
Adhesion-blocking antibodies were used to identify molecules responsible for Ca2+-independent adhesion. The antibodies precipitated surface molecules specific for adhesion-competent cells. These have tentatively been named CIDSBHK and CIDSpyBHK. Both were glycoproteins with respective apparent molecular weights of 120K and 125K. CIDSpyBHK incorporated 3H-glucosamine more than CIDSBHK did. Possible modification of the Ca2+-independent adhesion mechanism in pyBHK cells is discussed.View full abstractDownload PDF (852K) -
Hiroyoshi Hoshi, Mikio Kan, Isao Yamane, Tadao Ohno, Masayoshi Namba1983 Volume 8 Issue 1 Pages 67-75
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSSerum-free culture is a useful method for identifying the growth requirements of normal cells of human origin and comparing them to the re-quirements of transformed human cells. We examined differential growth requirements of serum factors (bovine serum albumin (BSA) and low density lipoprotein (LDL)) on normal (HEL), Co-60 gamma ray-transformed (CT-1) and 4-nitroquinoline 1-oxide-transformed (SUS M-1) human fibroblast cells in the absence of serum. A decreased requirement for serum was closely related to a decreased requirement for BSA in both types of transformed cells. The growth rate and saturation density of HEL and CT-1 cells grown in serum-free medium supplemented with the optimal concentrations of BSA were almost equal to the rates of cells grown in serum-supplemented medium. When BSA alone was added to the serum-free medium it did not support the continuous growth of SUSM-1 cells because of cellular detachment. An addition of LDL to serum-free cultures not only promoted the moderate growth of HEL cells, it promoted the continuous growth of SUSM-1 cells as well. In contrast, LDL was not required for the optimal growth of CT-1 cells. Transformed human cells specifically had reduced quantitative and qualitative growth requirements for one or more serum factors.View full abstractDownload PDF (975K) -
Yasuo Nakaoka, Takashi Oka, Kuniaki Serizawa, Hideki Toyotama, Fumio O ...1983 Volume 8 Issue 1 Pages 77-84
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSAcceleration of swimming velocity was induced by the transfer of Paramecium cells to solutions containing various multivalent cations, Fe3+, Ca2+, Mg2+, Tris+, and others. The monovalent cations, K+, Rb+, Li+ and Na+, however, suppressed the acceleration induced by the multivalent cations. Effects of Ca2+ and K+ on swimming velocity were antagonistic, as the Ca2+ concentration increased the K+ concentration acted to suppress the Ca2+ induced acceleration. As both the Ca2+ and K+ concentrations were low, this antag-onistic relation could be represented by the concentration ratio, [K+]/[Ca2+]1/2.
Acceleration of the swimming velocity took place when cells were transferred to a solution with a lower concentration ratio than that of the adapting solution used. Time courses of decreasing velocity after acceleration were examined at various concentrations of Ca2+ and K+, and for various temperatures. Change in membrane potential as measured with a microelectrode, was not consistently related to the change in swimming velocity. These results are discussed in relation to the driving force for the influx of Ca2+.View full abstractDownload PDF (718K) -
Yoshio Kawamoto, Takashi Muramatsu1983 Volume 8 Issue 1 Pages 85-87
Published: 1983
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSCellular sites of [3H]galactose incorporated into F9 embryonal carcinoma cells were determined by electronmicroscopic autoradiography. Fifty-six per cent of the label was on plasma membrane.View full abstractDownload PDF (309K)
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