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Volume 35, Issue 3
Displaying 1-6 of 6 articles from this issue
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Akio KUSANAGI, Nobunori TANAKA1960 Volume 35 Issue 3 Pages 67-70
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSThe distal sequence of Luzula purpurea chromosomes at meiotic prophase has been studied. The result obtained indicates that as shown in Figs. 2-11 a well differentiated structure which may imply the centromere structure has been confirmed on both distal parts of every chromosomes; this will support the third hypothesis refered to in the introduction. At the same time the presence of chiasmta in the bivalent chromosomes has also been suggested in contrast to the current opinion.View full abstractDownload PDF (788K) -
Koichiro TSUNEWAKI1960 Volume 35 Issue 3 Pages 71-75
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSConventional and monosomic analyses of the lethality occurring in diallel crosses of eight common wheat varieties led to the following conclusions:
(1) Lethality is controlled by two dominant complementary genes.
(2) The gene in Prelude is located on chromsome V and designated as Le1.
(3) The gene in Kharkov and Jones Fife is the same; it is located on chromsome XIII and designated as Le2.
(4) Chinese Spring, S-615, Red Bobs, Elgin and Red Egyptian carry the recessive normal alleles of both genes.
(5) The genetic penetration of the recessive normal gene is about 0.05%.
The experimental results indicate that monosomic analysis, using an incomplete monosomic series, can be successfully applied when a few major genes are involved in the inheritance of a specific character.View full abstractDownload PDF (481K) -
II. Effects of the Metamorphic Hormone (Cephalic Complex) upon Growth and Differentiation of Eye-Antennal Discs, and Strain Differences in Relation to the Metamorphic HormoneMasakatsu HORIKAWA1960 Volume 35 Issue 3 Pages 76-83
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESS1. Eye-antennal discs and cephalic complexes removed from mature third-instar larvae of a wild strain or various mutants of D. melanogaster were cultured in vitro in a synthetic medium, in order to invesitgate differences of metamorphic hormones among these strains.
2. Ten cephalic complexes of Oregon-R larvae provide in a hanging-drop culture the optimum concentration of the metamorphic hormone for promoting growth and differentiation of eye-antennal discs removed from the cephalic complexes of Oregon- R larvae.
3. The cephalic complex of various eye-color mutant larvae (bw, v, cn, v bw, cn bw or w) has a similar effect upon growth and differentiation of eye-antennal discs, secreting the metamorphic hormone.
4. The metamorphic hormone secreted from the endocrine organ in the cephalic complex of B, bar-3 or Dp/In(3L)p, In(3R)c, sbel(3)e larvae seems to be qualitatively different from that of Oregon-R or various other eye-color mutants. Dp/In(3L)p, - In(3R)c, sbel(3)e mutant seems to be different from B or bar-3 mutant in respect to the quantity of the metamorphic hormone, and the eye-antennal discs of this strain are not affected either by the metamorphic hormone of Oregon-R or various eye-color mutant larvae.
5. These facts suggest that the genic action appears simultaneously in both, cephalic complexes and eye-antennal discs.View full abstractDownload PDF (1172K) -
Michio TSUKAMURA1960 Volume 35 Issue 3 Pages 84-88
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSMutations to kanamycin resistance in Micrococcus pyogenes var. aureus. strain 209P, occur by way of an obligatory multi-step pattern, unlike the patterns of kanamycin resistance in mycobacteria, which are facultative single-step (facultative multi-step) patterns.
Kanamycin resistance is closely related with slow growth.
Mutations to kanamycin resistance were accompanied with simultaneous mutations to slow growth, and mutations to fast growth in slow-growing kanamycin-resistant mutants were accompanied with simultaneous mutations to kanamycin sensitiveness. It was suggested thus that both slow growth and kanamycin resistance belong to the same locus.View full abstractDownload PDF (442K) -
T. En WILLWEBER Née KISHIMOTO1960 Volume 35 Issue 3 Pages 89-94
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSThe present article deals with some cytological effects of para-oxybenzoicacidethylester on tumor cells of the MTK-sarcoma II, III and V, transplantable ascites tumors of rats, with particular regard to the morphological response of tumor cells to the drug. Intraperitoneal injections of the drug at dose level of 200, 300 and 400mg/kg were made in each tumor-bearing rat on the 3rd day after transfer of the tumor.
The drug seems to exert some injurious effects on nervous system of the treated animals, since they showed some difficulty in moving their hind legs for 10 to 30 minutes long after injection. The infiltration of tumor cells was observed in intraphragma and serosa of treated tumor animals, with hypertrophy in liver, spleen and kidney, though less remarkable in the latter two organs. The drug exerted a striking destructive influence on the tumor cells: 6-8 hours after injection, tumor cells were completely damaged in most cases studied. The effective duration of the drug seems to be comparatively short. Some tumor cells remained alive without damage by the drug: active tumor cells made their appearance 12 hours after injection, and formed a source of renewed tumor growth. Their life span was prolonged 1 to 2 days more.
Remarkable cytological effects of the drug on tumor cells are as follows: the deformation of nuclei and their resulting destruction were common in tumor cells after treatment. The reduction in stainability of nucleoli was remarkable in resting cells 1-2 hours after application. The drug seems to disintegrate nucleoli into tiny particles, resulting in the disturbance in function of the nucleus. Induced abnormalities of chromosomes leading to their disintegration are striking stickiness and aggregation at prophase and metaphase, and sticky bridges and lagging at ana-, telophase. The damage of the cytoplasm was also evident by the cytoplasmic swelling and blebbing of cell surface. In a more advanced condition the drug induced a formation of vacuoles in the cytoplasm.View full abstractDownload PDF (1690K) -
Hiroshi KAYANO, Masanobu SANNOMIYA, Kôya NAKAMURA1960 Volume 35 Issue 3 Pages 95-99
Published: 1960
Released on J-STAGE: May 21, 2007
JOURNAL FREE ACCESSIn a grasshopper, Acrida lata, some male specimens have been found to contain 1, 2, or 3 B chromosomes in addition to the normal complement 2n_??_=22+X, while others to contain none. The frequencies of the specimens with B's varied locally from 7 to 31 per cent according to the populations sampled, in 1959, from 9 localities in the northern part of Kyushu, Japan. In a population, which studied in succeeding 3 years from 1957 to 1959, the frequency of animals with B's slightly fluctuated from year to year, i. e., 32, 34, and 30 per cent in frequency. The B's of different populations were the same in cytological feature and behavior, suggesting their common origin in the remote past of the species. This in turn would explain why the same B's are distributed wide in natural populations. Mechanism of the population dynamics remains for further investigations.View full abstractDownload PDF (438K)
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