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551.
An effective reactivation of alkaline phosphatase in hard tissues completely decalcified for light and electron microscopy 总被引:2,自引:1,他引:1
Summary An effective procedure for reactivating alkaline phosphatase in tissues decalcified completely for light and electron microscopy was presented. It was indicated that an Mg ion supply as reactivator in the decalcified sections before, not during, incubation for demonstration of the enzyme was important. In addition, choice of buffer solutions as Mg ion solvent and as rinsing solution for the sections after reactivation were also important. Cacodylate buffer should not have been used as an Mg solvent because the reactivation effect of the Mg ion was seriously reduced. But it should have been used for rinsing reactivated sections in order to obtain reaction products at all sites of enzyme activity throughout thick sections used for electron microscopy. 相似文献
552.
M Umeda 《Microbiology and immunology》1987,31(2):113-121
The cationic carbocyanine dye, 1-ethyl-2-[3-(1-ethylnaphtho[1, 2d]-thiazolin-2-ylidene)-2-methylpropenyl]-naphtho[1, 2d]thiazolium bromide, interacts with several classes of anionic polymers, exhibiting metachromasia. We were able to stain various kinds of microorganisms with this dye. Gram-negative bacteria were stained reddish purple, while Gram-positive bacteria were stained violet or bluish purple. Stains of molds were of various colors. Yeast vegetative cells were stained reddish purple, but zygotic asci were bluish. Chlamydia trachomatis inclusions, which are surrounded by cytoplasmic membranes, were also stained red. Microorganism and cell stains have different features and can be identified also by use of fluorescent microscopy. The new staining method we report here is rapid and simple enough for routine microscopical examinations of smears of clinical specimens including microorganisms. 相似文献
553.
Strain ST67P of Staphylococcus hyicus grew diffusely in regular serum-soft agar. With the addition of rabbit antisera prepared with Staph. aureus strains, Smith, NS58D or NS41D, capsular type A, B or C, respectively, the organisms converted to compact type growth. Mice immunized with heat-killed vaccine of strain ST67P showed significant resistance against either homologous or heterologous strains, Smith, NS58D and NS41D. Passive protective activities in rabbit antisera prepared with strains Smith, NS58D and NS41D were absorbed out with either homologous cell surface polysaccharide fraction or cell surface polysaccharide fraction extracted from strain ST67P. Well-defined large capsules were observed in ultra-thin sections treated with rabbit antiserum prepared with homologous strain conjugated with ferritin. Also, the capsule surrounded by ferritin granules was shown in ultra-thin sections treated with ferritin conjugated with antisera prepared with those heterologous strains although the capsular size was significantly smaller than those observed by homologous antiserum. 相似文献
554.
Tsuyoshi Yamada Koichi Makimura Tatsuya Hisajima Yumiko Ishihara Yoshiko Umeda & Shigeru Abe 《FEMS microbiology letters》2009,298(2):208-217
The frequency of targeted gene disruption via homologous recombination is low in the clinically important dermatophyte, Trichophyton mentagrophytes . The Ku genes, Ku70 and Ku80 , encode key components of the nonhomologous end-joining pathway involved in DNA double-strand break repair. Their deletion increases the homologous recombination frequency, facilitating targeted gene disruption. To improve the homologous recombination frequency in T. mentagrophytes , the Ku80 ortholog was inactivated. The nucleotide sequence of the Ku80 locus containing a 2788-bp ORF encoding a predicted product of 728 amino acids was identified, and designated as TmKu80 . The predicted TmKu80 product showed a high degree of amino acid sequence similarity to known fungal Ku80 proteins. Ku80 disruption mutant strains of T. mentagrophytes were constructed by Agrobacterium tumefaciens -mediated genetic transformation. The average homologous recombination frequency was 73.3 ± 25.2% for the areA/nit-2 -like nitrogen regulatory gene ( tnr ) in Ku80− mutants, about 33-fold higher than that in wild-type controls. A high frequency ( c . 67%) was also obtained for the Tri m4 gene encoding a putative serine protease. Ku80 − mutant strains will be useful for large-scale reverse genetics studies of dermatophytes, including T. mentagrophytes , providing valuable information on the basic mechanisms of host invasion. 相似文献
555.
Yoshimasa Suda Takashi Umeda Kiyotaka Watanebe Jun Kuroiwa Eiji Sasaki Toshiaki Tsukamoto Ippei Takahashi Masashi Matsuzaka Kaori Iwane Shigeyuki Nakaji 《Luminescence》2013,28(2):121-128
We examined changes in neutrophil function of soccer players over a 10‐month period and determined its effectiveness as an index for athlete physical condition. Subjects included 21 male professional Japanese soccer players. Data on body composition, myogenic enzymes and neutrophil function were obtained before and after 2 h of training at 3 investigation points: one week before opening season, at season mid‐point, and one week before the last game of the season. As a result, change ratios of myogenic enzyme levels before and after the 2‐hr training session at the third investigation point were significantly higher compared to the two other points. Reactive oxygen species production and phagocytic activity significantly increased after 2‐hr training session at point 1, although the extent of the increase became smaller over time and ROS production capability decreased significantly by point 3 assessment. Fatigue, especially muscle fatigue, chronically accumulated along with a gradual decrease in neutrophil immune function over the 10‐month season. Therefore, determination of neutrophil function can be used as a useful index to assess and understand an athlete's physical condition. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
556.
It has been reported that fatty liver is not uncommon in Cushing's syndrome. Biochemical data obtained from routine blood chemistry in 10 patients with Cushing's syndrome were compared with those for 15 patients with histologically verified fatty liver. We found an absence of a decreased GOT/GPT ratio, low normal choline esterase and increased lactic dehydrogenase activities together with lowered serum protein and albumin, and increased blood sugar and total cholesterol in Cushing's syndrome when compared with those of fatty liver cases. These data and additional findings in liver histology obtained from one patient with Cushing's syndrome due to adrenocortical carcinoma indicated that fatty changes in the liver were not frequently encountered in Cushing's syndrome. These abnormal biochemical data might be a way of distinguishing Cushing's syndrome from fatty liver. 相似文献
557.
558.
Kazunobu Amako Norio Baba Nobuyuki Suzuki Sun Nyunt Wai Akiko Umeda 《Microbiology and immunology》1997,41(11):855-859
A negatively stained electron micrograph of regularly arranged porin proteins of Campylobacter jejuni on the isolated outer membrane of bacteria was analyzed in detail by the correlation averaging method using a computer-assisted program. The results showed that the porin of C. jejuni had a trimeric structure separated by about 10.4±0.15 nm. In addition, the pores in the trimers were also separated by about 4.3 ±0.1 nm. 相似文献
559.
Four types of IS1 with differences in nucleotide sequence reside in the Escherichia coli K-12 chromosome. 总被引:8,自引:0,他引:8
The Escherichia coli K-12 chromosome contains six copies of insertion element IS1 at loci is1A-is1F. We determined their nucleotide (nt) sequences and found that they were classified into four types. Two copies of IS1 which flank a chromosomal segment containing the argF gene (IS1B and IS1C) have identical nt sequences. Another identical pair are IS1A and IS1E. Comparison of their nt sequences with the IS1 in plasmid R100 revealed seven nt mismatches for IS1A (or IS1E), two for IS1B (or IS1C), four for IS1D, and 75 for IS1F. The fact that the IS1s flanking the argF segment are identical supports the idea that the segment, together with the particular pair of IS1s, has constituted a composite transposon and transposed after genetic transfer from another bacterial species into E. coli K-12. Duplicated sequences were not observed in the regions flanking each of four copies of IS1, indicating that rearrangements have occurred in these chromosomal regions after IS1 elements had been inserted into several target sites. The four types of IS1 present in the E. coli K-12 chromosome were essentially similar to IS1s in plasmid R100 and in the chromosomes of Shigella strains. This and the above results suggest that they have been transferred horizontally from other Enterobacteriaceae, including Shigella, into E. coli K-12. 相似文献