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Volume 1 (1975 - 1976･･･
- Issue 4 Pages 299-
- Issue 3 Pages 205-
- Issue 2 Pages 137-
- Issue 1 Pages 1-
Volume 1, Issue 3
Displaying 1-9 of 9 articles from this issue
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Yutaka Tashiro, Takeo Shimadzu, Shiro Matsuura1976 Volume 1 Issue 3 Pages 205-222
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSMeasurements of lysosomal enzyme activities (acid phosphatase, acid RNase, and cathepsin) and observations of electron microscopic cytochemical preparations were correlated with ultrastructural changes in the posterior silk gland cells during the late larval stadium of the silkworm Bombyx mori. In the fourth instar the lysosomal enzymes were synthesized exclusively in the feeding stage when the wet weight of the gland increased exponentially, and the enzymes were probably stored in Golgi bodies. In the molting stage a number of autophagosomes, autolysosomes and autophagic vacuoles appeared in the cells, and the lysosomal enzymes presumably played pivotal roles in the catabolic processes of the silk gland cells. In the early half of the fifth instar (0-96 h), a similar exponential increase in lysosomal enzymes was observed, and the synthesized enzymes were also probably stored in Golgi bodies. In the middle of the fifth instar (96 h) when the metabolism of the silk gland was changed from the growth phase to stationary phase, several characteristic structures appeared, such as lipid droplets, myelin structures and whorl structures of rough ER. In the latter half of the fifth instar, the lysosomal enzyme activities were stabilized temporarily then increased again slightly arriving at a maximum value at the end of the fifth instar.View full abstractDownload PDF (12174K) -
Shiro Matsuura, Takeo Shimadzu, Yutaka Tashiro1976 Volume 1 Issue 3 Pages 223-235
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSAcid phosphatase activity measures in various stages of the posterior silk gland cells of Bombyx mori suggested that the lysosomal enzyme used for degenerative and cytolytic processes in the prepupal-pupal stadium was not synthesized in the prepupal-pupal stadium but in the feeding stage of the fifth larval instar. The specific activity of the lysosomal enzymes (activity per unit weight of the gland) was rather low in the spinning period but increased rapidly after spinning was completed. Electron microscopic cytochemical observations revealed that the number of acid phosphatase positive granules per unit area peaked at about 36 h of the prepupal stadium, decreased once and then increased markedly towards the end of the prepupal stadium. Ultra-structural changes in the prepupal-pupal stadium also appeared to be biphasic. In the spinning period (prepupa 0-72 h), focal degenerative changes by the autophagosomes-autolysosomes system appeared preferentially near or at the canal zone in the apical and perinuclear cytoplasm. After completion of spin-ning, cytolytic processes became evident everywhere; the apical and perinuclear cytoplasm were digested extensively by the same autophagic mechanisms, and at the same time the basal cytoplasm and nucleus were partitioned and packed by smooth membranes. Thus the silk gland was fragmented into a number of globules containing cytoplasmic and/or nuclear components.View full abstractDownload PDF (13468K) -
Jeman Kim, Hiromi Mitsui, Yoshio Okada1976 Volume 1 Issue 3 Pages 237-249
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSMovements of HVJ envelope antigens integrated into Ehrlich ascites tumor cell membranes were observed during cell fusion reaction by electron microscopy using ferritin-conjugated anti-HVJ envelope antibody. Many fusion sites of viral envelopes with cell membrane were seen randomly on fused cell surfaces. The viral envelope antigens derived from individual virions were seen not dispersed but patched on the cell surface. On culture of fused cells, endocytosis of the cell membrane occurred at areas containing viral antigens. Antigens thus disappeared from the cell surface, and they were transferred to newly formed cytoplasmic vesicles, which were observed just under the cell membrane. On further incubation, vesicles containing viral antigens gathered to the base of the cytoplasmic projection. No vesicles containing viral antigens were observed at other areas of the cytoplasm. At this incubation period, cytoplasmic projection developed on one side of the cell. The surface of this projection was clustered by many microvilli-like protrusions. Some viral antigens were exposed on the protrusions. One possible mode of viral antigen accumulation to a specific site (like cap) of the fused cell may be by integration of viral antigens into vesicles by endocytosis of the cell membrane and re-exposure to a scheduled area of the cell by exocytosis.View full abstractDownload PDF (2307K) -
Yasuko Rikihisa, Shoji Ohkuma, Den'ichi Mizuno1976 Volume 1 Issue 3 Pages 251-258
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSReduction of nonspecific binding of ferritin conjugated to anti-rabbit IgG goat IgG with the aid of p, p'-difluoro-m, m'-dinitro diphenyl sulfone was investigated using the plasma membranes of guinea pig poly-morphonuclear leukocytes as antigen. The ferritin conjugate was labeled with 125I and fractionated by DEAE cellulose column chromatography into four fractions. Each fraction was incubated with the plasma membrane fractions, and fraction 2 eluted with a buffer of low ionic strength gave the least radio-activity bound to plasma membrane without specific antibody against the membrane (nonspecific binding). On further absorption of this fraction with plasma membrane, highly specific ferritin conjugate which showed only 1.2% of the nonspecific binding of unfractionated ferritin conjugate was recovered in the non-adsorbed fraction.View full abstractDownload PDF (5260K) -
Kanji Takeo, Tokio Nonaka, Teruyuki Ikeda1976 Volume 1 Issue 3 Pages 259-267
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSFreeze-etched preparations of sporangiospores of Rhizopus were examined for ultrastructural alterations during spore maturation and to determine when invaginations of the cell membrane appear in relation to these changes. First, membrane irregularly delimitated the sporangium. The mem-brane appeared thick. Then, the walls of the sporangiospore became apparent. Simple ridges appeared on the thin walls. Near wall surfaces, particle-like struc-tures were characteristically observable only in this stage of maturation. The cell membrane was devoid of invaginations, particulated less densely than the cell membrane of mature spores and concaved along the ridges. In cross-fractures, immature spores revealed a nucleus, lipid droplets and mitochondria, indistinct both in cristae and furrows of the membrane. Spores then resembled mature spores in shape but differed in the following points : (i) freeze-fracture was not observed along the spore surface; (ii) the ridges of the spore wall were etched deep, indicating a low content of structural material; and (iii) the cell membrane was devoid yet of invaginations. Other new findings on dormant spores were described, and the function of the cell membrane invaginations was discussed.View full abstractDownload PDF (8604K) -
Masakatsu Hato, Tetsuo Ueda, Kenzo Kurihara, Yonosuke Kobatake1976 Volume 1 Issue 3 Pages 269-278
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSPhototaxis of plasmodium of true slime mold Physarum polyce-phalum was studied as a function of light wavelength and intensity. The changein the motive force of protoplasmic streaming (ΔPt) or isometric tension (ΔF/Fo) was taken as the phototactic response. Three active spectral regionsexist in the action spectrum of phototaxis. The blue light region (λmax = 490nm)or far-red light region (λmax = 720nm) induced negative taxis, and the red lightregion (λmax = 650nm) led to positive taxis. The absorption spectrum of plas-modial yellow pigments did not coincide with the maxima of the action spec-trum. The time course of the phototactic response ΔPt was independent ofintensity for a given wavelength so far as the intensity of stimulating lightexceeded the threshold value, suggesting that light stimulation acted as atrigger for initiating the tactic movement. The mode of phototaxis resembledthat of chemotaxis for motive force, i.e., the steady value of phototactic motiveforce ΔP changed from zero to 8-12 cm H2O in rather narrow intensity regions, and ΔP values were independent of the intensity of light so far as the intensityexceeded the threshold value Ic. When the slime mold was illuminated withblue (500nm, 510nm) and far-red (720nm) light, isometric tension increasedwith the intensity of light (I>Ic) while for red light (650nm) isometric tensiondid not show an appreciable change on illumination.View full abstractDownload PDF (1063K) -
Isao Yamane, Osamu Murakami, Miwa Kato1976 Volume 1 Issue 3 Pages 279-284
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSA "serum-free" culture medium was developed supplemented with 1% bovine serum albumin. This medium promoted the growth of primary and continuous cultures of various mammalian tumor cells in suspension systems. The albumin bound lipid was found to play an important role in the serum-free culture.View full abstractDownload PDF (462K) -
Osamu Murakami, Isao Yamane1976 Volume 1 Issue 3 Pages 285-290
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSThe effect of basic polymers on cell growth was investigated with Yoshida ascites sarcoma cells cultured in "serum-free" medium containing a small amount of bovine serum albumin (BSA) and fatty acids (linoleic and oleic acids). Basic polymers per se had little, if any, effect on cellular growth, but when added with appropriate amounts of BSA and fatty acids, basic polymers synergistically induced a marked cellular proliferation. Among basic polymers studied so far, the highly basic poly-L-arginine and polyethyleneimine were most effective. The optimal concentrations of basic compounds for cell growth enhancement decreased in inverse proportion to their molecular weight.View full abstractDownload PDF (667K) -
Takashi Ikegami, Ryosaburo Takaki, Michio Fukuma, Junko Ono1976 Volume 1 Issue 3 Pages 291-297
Published: 1976
Released on J-STAGE: April 18, 2008
JOURNAL FREE ACCESSOrgan culture of the pancreatic islets of a 14-day old WKA rat was achieved on a millipore filter supported by a small petri dish filled with liquid medium. During the 9-day culture period, the architecture of the islets was preserved. Morphological alterations of B cells were found under electron microscopy after increasing the concentration of glucose. These changes in B cells included degranulation and formation of well-developed rough endoplasmic reticulum. A few mitotic figures were observed among B cells of islets cultured with glucose at 3 mg per ml for nine days. The morphological observations were supported by radioimmunoassay of insulin-release into the medium. Organ-cultured islets in 3 mg per ml of glucose released approximately nine times as much insulin into the medium during each three day period assayed as islets in 1 mg per ml of glucose. This culture system provides a useful tool for investigating the effects of various agents on the function of islet cells for prolonged periods in vitro.View full abstractDownload PDF (7078K)
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