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11.
Ritsuko Katoh-Semba Reiji Semba Hiroyuki Kato† Masataka Ueno† Yoshihiro Arakawa† Kanefusa Kato‡ 《Journal of neurochemistry》1994,62(6):2141-2147
Abstract: Our previous studies showed that the concentration of the β subunit of nerve growth factor (β-NGF) in nervous tissues is higher in male than in female mice. To identify the brain regions that are affected by androgens, the amounts of β-NGF protein and its mRNAs were measured in male, female, and castrated male CD-1 mice and testicular feminization mice at 3–4 months of age. Among tissues examined, the hypophysis of males contained the highest average concentration of β-NGF protein. In most regions of the brain, individual levels were more variable in males than in females. However, after the castration, such variations in β-NGF levels disappeared. Average levels of β-NGF protein in males were higher in the cerebellum (eightfold higher), olfactory bulb (12-fold higher), hypothalamus (sixfold higher), and hypophysis (72-fold higher) than thope in corresponding regions of females. No significant differences were observed in levels of β-NGF protein in the hippocampus, cerebral cortex, striatum, septum, and brainstem. The castration of male mice caused a reduction in levels of β-NGF protein in the hypothalamus and hypophysis, but not in the cerebellum and olfactory bulb, to the femgle levels. The concentrations of β-NGF protein in testicular feminization mice were similar to those in female CD-1 mice in all regions. The concentrations of mRNA for β-NGF in the olfactory bulb and hypophysis from males were higher than those from females. By contrast, northern blots showed no remarkable differences in the amounts of brain-derived neurotrophic factor and neurotrophin-3 between the two sexes. Thus, in some regions of the brain, the production of β-NGF appears to be regulated by testosterone, but the regulatory mechanisms do not appear to be simple. Our present results indicate that the binding of testosterone to its receptor is an important step in the regulation of the level of β-NGF in these region. 相似文献
12.
Genetic transformation in Helicobacter pylori was investigated by using its chromosomal and plasmid DNAs. Six out of the eight strains exhibited the natural competence for incorporation of H. pylori chromosomal DNA, and all the strains incorporated the donor DNA efficiently by washing and concentrating the cells, with a glycerol solution. The much higher frequency of transformation was obtained in each strain by means of electroporation. Electroporation experiments were also conducted by use of the recombinant DNAs consisting of the H. pylori and Escherichia coli plasmids as the donors, and the occurrence of the homologous recombination was demonstrated between the incoming H. pylori plasmid-derived region and the corresponding region of the originally residing plasmid in H. pylori. 相似文献
13.
An axenic clonal culture of Chattonella antiqua (Hada) Ono was grown on a 12: 12 h LD cycle in a laboratory culture tank containing 1 m3 of f/2 medium. Diel changes in mean cell volume, cellular carbon (carbon content per cell), C/N ratio, cellular Chl a, Chl a/c ratio and carotenoid composition were observed. Mean cell volume and cellular C, N and pigments increased during the light period as a result of photosynthesis and decreased with increase of cell concentration by phased cell division during the dark period. These changes indicated that carbon assimilation and pigment synthesis occurred together during the light period. However, the patterns of increase were not the same since different diel patterns were also found in the ratios of C/N and chl a/c. Photosynthetic pigments were analyzed by reversed-phase high-performance liquid chromatography with ion-pairing solution. This analysis showed that the dominant carotenoids in C. antiqua were fucoxanthin, violaxanthin and β-carotene. Diel patterns of Chls a and c were similar to that of fucoxanthin but different from those of violaxanthin and β-carotene. The cellular contents of Chl a, fucoxanthin and carbon increased in a parallel manner during the light period. On the other hand, the increase of violaxanthin was restricted to only a few hours at the beginning of the light period during cell division cycles. 相似文献
14.
Joji Sekine Kazuo Sano Masataka Uehara Tsugio Inokuchi 《Biotechnic & histochemistry》1996,71(3):152-156
A technique Is described for rapid detection of S-pha?e cells of tumor tissues in smear specimens using bromodeoxyuridine (BrdU) immunostaining. Mouse NR-S1 tumors and human tumor specimens were prepared for smear cytology after incubation in RPMI 1640 culture medium containing 200 μM BrdU at 37 °C under 3 atm for 1 hr. Samples were fixed in 70% ethanol for 30 min and used immediately or air dried for 30 min. Samples were then denatured in either 4 N HC1 or 0.07 N NaOH to prepare partially single-stranded DMA. Fixation with air drying for 30 min followed by 30 min in 70% ethanol and 1 min denaturation with 0.07 N NaOH resulted in satisfactory staining quality. Cultured tumor specimens were processed for routine paraffin sections after smears were made for cytology. The labeling indices of the smear specimens and of the paraffin sections gave similar results. This technique should be useful in evaluating the cell proliferative potential of tumor tissue in smear cytology without processing paraffin sections. 相似文献
15.
16.
Masataka Obika Szecheng J. Lo T. T. Tchen Dr. John D. Taylor 《Cell and tissue research》1978,190(3):409-416
Summary The hormone-induced pigment dispersion in primary cultures of xanthophores of goldfish (Carassius auratus L.) has been shown to involve the dispersion of not only carotenoid droplets but also of smooth endoplasmic reticulum. The dispersion of these organelles is inhibited by cytochalasin B and is accompanied by thinning of the cell body, thickening of the processes, and also overall changes in cellular morphology (process extension) under certain conditions. Electron microscopic examination of heavy meromyosin treated glycerinated xanthophores in scales revealed the presence of actin filaments in these cells.This work was supported, in part, by grants AM-5384 and AM-13724 from U.S.P.H.S. 相似文献
17.
Yoshiteru Harada Kunio Tanaka Kowa Yamashita Masataka Ishibashi Hiroshi Miyazaki Makoto Katori 《Prostaglandins & other lipid mediators》1983,26(1):79-90
Intrapleural injection of 2% λ-carrageenin caused the accumulation of exudate up to 19 hr. The rate of plasma exudation, measured by the exuded dye amounts for 20 min in the pleural cavity after intravenous injection of pontamine sky blue, showed a peak at 5 hr. Aspirin (100 mg/kg, i. p.) suppressed the dye exudation up to 5 hr, but did not at 7 hr. This inhibition coincided with the decrease of the PG and TXB2 levels, which were measured by gas chromatography-mass spectrometry, in the pleural exudate. In vitro experiments, MK-447, a phenolic compound, stimulates PG endoperoxide biosynthesis at lower doses and inhibits it at higher doses, acting as a tryptophan-like cofactor required by PG endoperoxide synthetase. This drug (0.3, 1.0 and 3.0 mg/kg, i. p.) suppressed the dye exudation dose-dependently up to 5 hr, but did not at 7 hr even at a higher dose, in combination with the dose-dependent decrease of the pleural level of PGE2, which was reported to be a major PG among PGs and TXB2 in the exudate in inducing the plasma exudation (Harada
; Prostaglandins,
: 881, 1982). Thus, the anti-inflammatory action of MK-447 can be explained by inhibition of PGE2 generation, giving no consideration to the role of oxygen-derived free radicals as a prime mediator in inflammation. 相似文献
18.
Kunshan Gao Yusho Aruga Kozi Asada Toshiaki Ishihara Toru Akano Masataka Kiyohara 《Journal of applied phycology》1991,3(4):355-362
Leafy thalli of the red algaPorphyra yezoensis Ueda, initiated from conchospores released from free-living conchocelis, were cultured using aeration with high CO2. It was found that the higher the CO2 concentration, the faster the growth of the thalli. Aeration with elevated CO2 lowered pH in dark, but raised pH remarkably in light with the thalli, because the photosynthetic conversion of HCO 3 ? to OH? and CO2 proceeded much faster than the dissociation of hydrated CO2 releasing H+. Photosynthesis of the alga was found to be enhanced in the seawater of elevated dissolved inorganic carbon (DIC, CO2 + HCO 3 ? + CO 3 ? ). It is concluded that the increased pH in the light resulted in the increase of DIC in the culture media, thus enhancing photosynthesis and growth. The relevance of the results to removal of atmospheric CO2 by marine algae is discussed. 相似文献
19.
Yoshiteru Harada Kunio Tanaka Yasushiro Uchida Akinori Ueno Sachiko Oh-ishi Yamashita Kowa Masataka Ishibashi Hiroshi Miyazaki Makoto Katori 《Prostaglandins & other lipid mediators》1982,23(6)
Injection of γ-carrageenin into t he pleural cavity of rats caused the accumulation of the pleural exudate. When levels of prostaglandins (PGs) and thromboxane (TX) B2 were quantified by gas chromatography-mass spectrometry as their methyl ester (ME)-dimethyllisopropylsilyl (DMiPS) ether or ME-methoxine-DMiPS ether derivatives, 6-keto-PGF1α reached the maximum at 1 hr after carrageenin, then PGE2 and TXB2 showed peaks at 3 hr and waned off before 9 hr. he PGF2α level was kept low, but PGD2, PGE1 and PGF1α were not detected. Aspirin (100 mg/kg, i.p.) significantly decreased the PG and TXB2 levels and suppressed the rate of plasma exudation until 5 hr, but did not at 7 hr, when it was measured by the amount of exuded pontamine sky blue injected intravenously. OKY-025 (300 mg/kg, i.p.), a selective TXA synthetase inhibitor, and tranylcypromine (20 mg/kg, i.p.), a PGI synthetase inhibitor, could not extensively inhibit the accumulation of the exudate. These results suggest that the cyclooxygenase products of arachidonic acid, particularly PGE2, definitely play an important role in the exudation during the first 5 hr. 相似文献
20.
Noriyoshi Uehara Shigeru Shirakawa Haruto Uchino Yukikazu Saeki Mitsuhiro Nozaki 《Life sciences》1980,26(6):461-467
Ehrlich ascites carcinoma cells (4×105 cells/mouse) were inoculated intraperitoneally in 7-week-old SLC:ICR mice, and polyamine levels in peripheral erythrocytes and in ascites cells were determined periodically. Polyamine levels in peripheral erythrocytes increased linearly until 10 days after cell inoculation, while ascites cells showed exponential growth.The effect of carbazilquinone on cellular growth and polyamine levels in erythrocytes was also studied. When 1 or 2mg/kg of carbazilquinone was injected intraperitoneally on day 4 or on day 7, cellular growth was suppressed and the survival time of the mice was lengthened. The polyamine levels in erythrocytes were also markedly decreased 3 days after the carbazilquinone injection.These results suggest that the polyamine levels in peripheral erythrocytes are closely related to the cellular growth of Ehrlich ascites carcinoma cells. 相似文献