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11.
12.
Trans-Stilbene oxide (TSO, 2 mmol/kg, ip.) induced ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (SAMDC) to 60-fold and 5-fold of the controls, respectively, in the liver of rats. Parallel to ODC induction, there was a marked increase in putrescine content to 50-fold of the control levels. Cis-Stilbene oxide (CSO), a stereoisomer of TSO, also produced the induction of ODC and SAMDC and the increase in putrescine content. There was no difference in the ability to induce ODC and SAMDC between TSO and CSO with respect to the extents of induction and the time needed to reach maximal levels. Trans-Stilbene (TS), a mother compound of TSO, did not show such an effect on ODC, while cis-stilbene (CS) induced both ODC and SAMDC. Treatment with glutathione inhibited TSO- and CSO-mediated induction of ODC and SAMDC. These findings add new information concerning the abilities of TSO, CSO and CS on hepatic polyamine metabolism. 相似文献
13.
Correction of inverted nipple with periductal fibrous flaps. 总被引:4,自引:0,他引:4
Y Megumi 《Plastic and reconstructive surgery》1991,88(2):342-346
I devised a method to correct the inverted nipple considering the preservation of the lactiferous ducts, sensory fibers to the nipple, and the contracting function of the areolar muscle. Excision of the excess skin at the base of the nipple was done in three diamonds fashion, and they were located at 2, 6, and 10 o'clock positions not to jeopardize the sensory fibers to the nipple. To release the fastened nipple, the periductal fibrous tissue was thoroughly dissected and made into three flaps pedicled inferiorly. These three flaps were sutured to the dermis of the periareolar skin to pull up the nipple base by means of traction in three directions. The purse-string suture, the dermal stitch on the shorter diagonals of the diamond-shaped defects, anchors the skin-muscle bridges caught at the base of the ductal column, makes the nipple base narrower, obtains stable anchoring, helps the areolar muscle contraction to resume, and prevents the recurrence of the inversion. The use of the periductal tissue as flaps to bring in areolar skin for easier anchoring and for more prominent eversion of the nipple has not been described in the literature. 相似文献
14.
Kiyoshi Matsuura Masayuki Takasugi Yasumasa Kunifuji Akio Horie Akio Kuroiwa 《Biological trace element research》1991,31(2):171-182
Twenty-four male rats of the Wistar strain divided into four groups were injected sc with a dose of 0.8, 1.5, and 3.0 mg Cd/kg body wt as CdCl2 in saline, and saline alone to the control rats, three times a week for 3 wk. Cadmium levels of whole kidney homogenate, supernatant (cytosol), precipitate, and metallothionein (MT) fraction were measured. Histological changes of the renal proximal tubules were investigated by optical and electron microscopy. In the kidneys, Cd levels were increased with the increment of Cd dosage; 80–90% of Cd was contained in cytosol, and 55–75% was in MT fraction. Non-MT-Cd reached a maximum in the 1.5 mg Cd group, whereas that of the 3.0 mg Cd group showed some decline. With increasing Cd doses, the size of nuclei and nucleoli in the cells of proximal tubule showed significant enlargement and also an increase in the number of nucleoli on light microscopy. At higher doses, chromatin condensation of the tubular nuclei and vacuolar degeneration of the tubular cells were evident. On electron microscopy, perichromatin granules of the proximal tubular nuclei were increased in number, especially in the rats of Cd 0.8 mg and 1.5 mg/kg groups. As the Cd doses increased, ring-shaped nucleoli were increased in number and nucleolar segregation was observed more clearly. Moreover, in the 3.0 mg/kg Cd group, nuclear indentation and nucleoli containing compact dense granules were observed. In the cytoplasm, there was an increase of lysosomes, myelin bodies, ring-shaped mitochondria, and vesiculation; ultimate changes were degeneration and cell necrosis. The injured cells were heterogenously distributed in each nephron and this heterogeneity was attributed in the difference in Cd content and cell cycle in each cell of the nephron. 相似文献
15.
Metabolism of galactosylceramide in the twitcher mouse, an animal model of human globoid cell leukodystrophy 总被引:2,自引:0,他引:2
The metabolism of galactosylceramide was investigated in normal and twitcher mice, an animal model for human globoid cell leukodystrophy. The findings were compared with data obtained on human tissues. In vitro studies demonstrated that there were two genetically distinct enzymes that hydrolyze galactosylceramide: galactosylceramidase I and II. The former was deficient in the twitcher, while the latter was intact. beta-Galactosidase preparations purified from normal mouse liver possessed the activity to hydrolyze galactosylceramide when the assay conditions for galactosylceramidase II was used. Therefore, galactosylceramidase II was considered to be identical to GM1 ganglioside beta-galactosidase. In contrast to the human enzyme, the murine beta-galactosidase had a relatively high Km value toward galactosylceramide. The galactosylceramide-loading test demonstrated that the twitcher fibroblasts hydrolyzed the lipid at lower rates than seen in cases of human globoid cell leukodystrophy fibroblasts. These differences in galactosylceramidase II between murine and human tissues suggest that galactosylceramide accumulates in twitcher mice but not in humans with globoid cell leukodystrophy, even though galactosylceramidase I is genetically deficient in both human and this mouse model. 相似文献
16.
Changes in morphology of chloroplast nuclei (cp-nuclei), totalcp-DNA content, number of cp-nuclei, oxygen-evolution activityand chlorophyll (a and b) content were examined during the degenerationand development of chloroplasts, using Chlamydomonas reinhardiicells which had been incubated on solid medium for various periods. Under 4'-6-diamidino-2-phenylindole (DAPI) epifluorescence microscopy,each cell that had been incubated for 7 days had one cell nucleus,one cup-shaped chloroplast and about 10 small, dispersed cp-nucleiin the chloroplast. One day after incubation of these cellson fresh medium, the cell volume and cp-nuclei increased insize 2-3 fold, but rapidly decreased in size after cell division.After about 7 days of incubation, cells ceased to divide andcp-nuclei began to associate with each other. At about 20 daysthey formed a ring-shaped structure surrounding the pyrenoid,followed by condensation into one cp-nuclear particle near thepyrenoid. When 41-day-old cells, having only one cp-nucleus,were reinoculated on fresh solid medium, the cp-nucleus increasedin size 23 fold, divided into several cp-nuclear particlesand then dispersed into the chloroplast, forming a bead-likestructure, before cell division. From microscopic fluorometry,a 4-fold increase in total cp-DNA content per chloroplast, withoutan increase in the number of cp-nuclear particles per chloroplast,occurred one day after the start of the experiment and one dayafter reinoculation of 41-day-old cells onto fresh medium. Theprocess of condensation of dispersed cp-nuclear particles intoone cp-nucleus during degeneration of the chloroplast was notaccompanied by any change in total cp-DNA content per chloroplast.A large peak of oxygen-evolution (0.60.9 pmoles/cell/hour)was seen one day after inoculation and reinoculation of thecells. The chlorophyll content (a+b) was high (1.22.2pg/cell) during the first week of incubation, after which itgradually decreased. (Received December 18, 1985; Accepted April 2, 1986) 相似文献
17.
Yasunobu Antoku Tetsuo Sakai Kohsuke Tsukamoto Ikuo Goto Hiroshi Iwashita Yoshigoro Kuroiwa 《Journal of neurochemistry》1985,44(6):1667-1671
Phospholipid classes that included plasmalogens of erythrocyte membranes in seven myotonic dystrophy (MyD) patients and seven normal controls were analyzed by HPLC. No significant difference in phospholipid classes was found between patients with MyD and normal controls, but there was a visible difference in peak profiles of compounds of the phosphatidylethanolamine class. In the study of plasmalogens, we used two preparation methods: exposure to HCl and deacylation with mild alkaline. The area ratio of the plasmalogen form to the diacyl form in the phosphatidylethanolamine class of MyD erythrocyte membranes was significantly lower than that of normal controls. Fatty acid analyses showed that fatty acids of both phosphatidylethanolamine subclasses have less unsaturation in MyD. 相似文献
18.
Human indolylamine 2,3-dioxygenase. Its tissue distribution, and characterization of the placental enzyme. 总被引:8,自引:0,他引:8
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The presence of indolylamine 2,3-dioxygenase was examined in human subjects by determining its activity with L-tryptophan as substrate. Enzyme activity was detected in various tissues, and was relatively high in the lung, small intestine and placenta. Human indolylamine 2,3-dioxygenase, partially purified from the placenta, had an Mr of about 40 000 by gel filtration and exhibited a single pI of 6.9. The human enzyme required a reducing system, ascorbic acid and Methylene Blue, for maximal activity and was able to oxidize D-tryptophan, 5-hydroxy-L-tryptophan as well as L-tryptophan, but kinetic studies indicated that the best substrate of the enzyme was L-tryptophan. 相似文献
19.
Megumi Kono Koji O'hara Yoshihiro Arai Hideyuki Fukuda Misaki Asakawa Hideomi Nakahara 《FEMS microbiology letters》1985,28(2):213-217
Abstract A susceptibility of 63 clinical isolates of Klebsiella pneumoniae to inorganic and organic mercuric compounds was determined. 18 of them were found to be resistant to fluorescein mercuric acetate (FMA) and merbromin (MB). Moreover, all the resistant strains inactivate the antibacterial effect of FMA. The changes in the amount of organic mercury at the time of inactivation of the drug and the structures of the end products were examined in detail with the plasmid-bearing strain JK9 and its transconjugants of Escherichia coli .
The results showed that FMA was inactivated by an intracellular enzyme produced inducively and was degraded to fluorescein (sodium salt, uranine), which led to the sedimentation of metallic mercury. The discovery of the genes conferring inducible organic mercury-inactivating enzymes determined by plasmids was the next step and their application in the recovery of metallic mercury from organomercurials is now imminent. 相似文献
The results showed that FMA was inactivated by an intracellular enzyme produced inducively and was degraded to fluorescein (sodium salt, uranine), which led to the sedimentation of metallic mercury. The discovery of the genes conferring inducible organic mercury-inactivating enzymes determined by plasmids was the next step and their application in the recovery of metallic mercury from organomercurials is now imminent. 相似文献
20.
Summary Dynamic change of plastid nucleoids (pt nucleoids) was followed by fluorescence microscopy after staining with 46-diamidino-2-phenyl indole (DAPI). The fluorescence image was quantified with a supersensitive photonic microscope system based on photon counting and image analysis. The results showed that small pt nucleoids located in the center of proplastids in the dry seed increased in size after imbibition and formed highly organized ring structures in the dark, which divided into ca. 10 pieces within 3 days. Corresponding to this morphological change, DNA content of a plastid multiplied 7.5 fold. Total increase in DNA content of pt nucleoids per cell was 34 times as that of dry seed, as plastid multiplied 4.6 times in the average during this period. Upon light illumination small pt nucleoids having basic genome size were separated from divided pt nucleoids, suggesting a relationship with the formation of thylakoid system. The significance of the procedure established in this study is discussed in analysing the dynamic changes of intracellular small genomes.On leave from Department of Biology, Faculty of Science, Nagoya University, Furocho, Chikusaku, Nagoya 464, Japan. 相似文献