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1.
Eleven temperature-sensitive mutants of adenovirus type 12, capable of forming plaques in human cells at 33 C but not at 39.5 C, were isolated from a stock of a wild-type strain after treatment with either nitrous acid or hydroxyl-amine. Complementation tests in doubly infected human cells permitted a tentative assignment of eight of these mutants to six complementation groups. Temperature-shift experiments revealed that one mutant is affected early and most of the other mutants are affected late. Only the early mutant, H12ts505, was temperature sensitive in viral DNA replication. Infectious virions of all the mutants except H12ts505 and two of the late mutants produced at 33 C, appeared to be more heat labile than those of the wild type. Only H12ts505 was temperature sensitive for the establishment of transformation of rat 3Y1 cells. One of the late mutants (H12ts504) had an increased transforming ability at the permissive temperature. Results of temperature-shift transformation experiments suggest that a viral function affected in H12ts505 is required for “initiation” of transformation. Some of the growth properties of H12ts505-transformed cells were also temperature dependent, suggesting that a functional expression of a gene mutated in H12ts505 is required to maintain at least some aspects of the transformed state. 相似文献
2.
3.
Kiyoshi Takamuku Tsuyoshi Akiyoshi Hideo Tsuji 《Cancer immunology, immunotherapy : CII》1987,25(2):137-140
Summary Antibody-dependent cell-mediated cytotoxicity (ADCC) mediated by a murine monoclonal antibody against human colerectal carcinoma, antibody 19–9, with human effector cells was tested in 33 patients with various carcinomas, 16 patients with benign lesions, and 13 normal controls, using a 12-h 51Cr release assay using human colorectal cancer cells as targets. Peripheral blood mononuclear cells (PBM) from these groups of patients and normal controls achieved moderate levels of target cell lysis in the presence of the monoclonal antibody at the high effector to target cell ratio of 200:1. The ADCC activity of PBM in cancer patients was significantly higher than that in either normal persons or patients with benign lesions. Since the ADCC was shown to be mainly mediated by adherent monocytes in the PBM, ADCC activity of monocytes from cancer patients was compared to those from control groups at an effector to target cell ratio of 30:1. The results also showed that the lytic capacity of monocytes was significantly higher in cancer patients than that in the control populations. 相似文献
4.
Scale Arrangement Pattern in a Lepidopteran Wing. 1. Periodic Cellular Pattern in the Pupal Wing of Pieris rapae 总被引:1,自引:1,他引:0
In most species of lepidopteran insects, anteroposterior rows formed by scales are arranged at regular intervals in the adult wing; within each row two kinds of scales are alternately arranged. To investigate the cellular basis for the scale arrangement pattern, we examined cell arrangement in the epidermal monolayer of the pupal wing of a small white cabbage butterfly, Pieris rapae , by scanning electron microscopy and light microscopy.
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
5.
6.
Nobutaka Fujii Akira Otaka Susumu Funakoshi Toshihiro Watanabe Hiromitsu Arai Kiyoshi Bessho Haruaki Yajima 《Journal of Protein Chemistry》1988,7(2):151-156
Treatment of a mixture of Cys(R)(O) and Cys(R) with an acid was found to generate cystine in fairly good yields, when suitable R, R, and an acid were selected. An unsymmetrical cystine peptide was prepared by treatment of a mixture of Z(OMe)-Cys(R) (0)-Ala-NH2 (R=Acm or MBzl) and Z(OMe)-Cys(MBzl)-Gly-OBzl with TFA or 1 M TFMSA/TFA.3 Oxytocin was obtained in an excellent yield by TFA treatment of the protected peptide containing Cys(Acm)(0) and Cys(MBzl). Thus, formation of the disulfide bond was found feasible at the position of Cys(R) (0).The following abbreviations are used Boc
t-butyloxycarbonyl
- Z(OMe)
p-methoxybenzyloxycarbonyl
- MBzl
p-methoxybenzyl
- Acm
acetamidomethyl
- Bzl
benzyl
- Ad
l-adamantyl
- tBu
t-butyl
- TFA
trifluoroacetic acid
- TFMSA
trifluoromethanesulfonic acid
- TMSOTf
trimethylsilyl trifluoromethane sulfonate 相似文献
7.
Dr. Emiko Matsumoto Kazushige Hirosawa Kiyoshi Takagawa Yoshiki Hotta 《Cell and tissue research》1988,252(2):293-300
Summary A Drosophila visual mutant rdgA has photoreceptive cells which degenerate gradually after eclosion. Fine structure of the retinular cells of rdgA
KS60
and rdgA
K014
was studied during early stages of degeneration to determine the initial morphological defects. The retinular cells of these two alleles showed the following structural abnormality within 1 day after eclosion: (1) rhabdomeres were small and irregular in shape; (2) cisternae of the rough endoplasmic reticulum were more numerous than those in normal retinular cells; (3) submicrovillar cisternae were absent; and (4) lysosomes were fewer than normal. Three-dimensional reconstruction of serial sections of the ommatidia showed that the degeneration of mutant rhabdomeres proceeds more rapidly in regions remote from the nuclei. These results suggest that the process of turnover of rhabdomeric microvilli is abnormal in rdgA. We also confirmed an increase of lysosomes and destruction of cellular organelles, as reported by previous investigators at more advanced stages of degeneration. 相似文献
8.
Kiyoshi Morikawa Jun-ichi Hamada Toshiyuki Itaya Makoto Ishikawa Noritoshi Takeichi Masuo Hosokawa Hiroshi Kobayashi 《Cancer immunology, immunotherapy : CII》1988,26(1):18-22
Summary Rat fibrosarcoma cells infected with Friend leukemia virus (FV-KMT-17) grow for a short time and then regress spontaneously in syngeneic hosts. This regression mechanism was examined by analyzing the immunomodulating action of the antitumor drugs busulfan (BU) and cyclophosphamide (CY). In preliminary experiments, the optimum dosages of BU and CY for the enhancement of DTH responses to SRBC were 10 mg/kg and 40 mg/kg respectively. Treatment of rats with BU (10 mg/kg) on day 5 induced the regression of KMT-17 cells, while in contrast, the same drug delayed the spontaneous regression of FV-KMT-17 cells. Pretreatment with CY (40 mg/kg) on day 5 did not affect the growth of KMT-17 or FV-KMT-17 cells. After the same treatment schedule, BU inhibited humoral antibody formation against SRBC and against virus-associated antigen (VAA), NK cell activity, and ADCC effector cell activity. On the other hand, CY did not affect the activities of NK cells or ADCC effector cells, although it significantly augmented the DTH responses to SRBC and the production of antibody to VAA but had no effect on production of antibodies to SRBC. These results suggest that NK cells and ADCC may play an important role in the initial stage of the spontaneous regression of FV-KMT-17 cells.Supported in part by a Grant-in-Aid for Cancer Research from the Japanese Ministry of Education
Abbreviations used: BU, busulfan; CY, cyclophosphamide; PFC assay, plaque forming cell assay; VAA, virus-associated antigen; NK cell, natural killer cell; ADCC, antibody dependent cellular cytotoxicity; MuLV, murine leukemia virus; DTH, delayed type hypersensitivity; SRBC, sheep red blood cells; C.I., cytotoxic index; CRBC, chicken red blood cells; IL-1, interleukin 1; IL-2, interleukin 2; IFN, interferon 相似文献
9.
Esaka Muneharu; Imagi Jun; Suzuki Kanichi; Kubota Kiyoshi 《Plant & cell physiology》1988,29(2):231-235
Ascorbate oxidase activity rapidly increased during callus formationfrom pumpkin fruit tissue. The activity reached a maximum at5 days after transfer and then declined. In callus which hadbeen subcultured at about 4-week intervals for more than oneyear, the activity also increased after transfer to fresh mediumand reached a maximum in the early logarithmic phase of growth.Light had little effect on the appearance of ascorbate oxidaseactivity in pumpkin callus. In the callus grown in the presenceof 10µM CuSO4, the activity was about 10 times that inthe presence of 0.1 µM CuSO4, suggesting that the formatonof ascorbate oxidase in pumpkin callus is stimulated by copper,a prosthetic metal of the enzyme. From 45 to 75% of the totalascorbate oxidase activity in pumpkin cell suspension cultureswas found in the medium. Ascorbate oxidase activity in the medium,as well as that in the cells, increased soon after transferto fresh medium, and reached a maximum at about 5 days. (Received July 2, 1987; Accepted November 21, 1987) 相似文献
10.
Kiyoshi Akeo Yasuhiko Tanaka Tatsuji Fujiwara 《In vitro cellular & developmental biology. Plant》1988,24(7):705-710
Summary The endocytotic process in cultured human RPE cells was observed after 1 min, 20 min, and 2 h incubation with cationized ferritin.
Within 1 min the ferritin particles were seen to attach to the cell membrane, especially between microvilli. Uncoated and
coated pits could be recognized on the cell membranes, and uncoated and coated endocytotic vesicles were found in the cytoplasm
after 20 min of incubation. These vesicles were surrounded by abundant microfilaments and had no visible membranes. Loss of
membrane may be an initial step in the process of developing into the irregular clumps of ferritin particles found inside
the plasma membrane. With time, more irregular clumps of ferritin, smaller than the particles introduced during incubation,
appeared just beneath the cell membrane. Lysosomes were adjacent to the clumps of ferritin particles associated with microtobules
and finally degraded these particles. The phagolysosomes containing many particles were surrounded by many microtubules. Small
ferritin particles surrounded but had not entered the rough endoplasmic reticulums, and no particles were seen either around
or in the Golgi apparatus.
Presented at the 7th International Congress of Eye Research, Nagoya, Japan, 27 September 1986. 相似文献