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11.
12.
Angiokeratoma corporis diffusum (Fabry's disease) is an X-linked disorder of glycosphingolipid catabolism. Heterozygous females, although usually asymptomatic, are occasionally as severely afflicted as hemizygous males; recently we identified a heterozygous patient with cardiomyopathy and severe pain in the extremities. In order to elucidate the difference of the clinical features, we analyzed the glycolipid composition of the heart, liver, and kidney obtained from the patient and from a hemizygote. Gas-liquid chromatography revealed that globotriaosylceramide (Gb3) was markedly increased in the heart (32.4 times higher than control) and increased to a lesser extent in the liver and kidney (3.74 and 6.79 times, respectively). The pattern of Gb3 accumulation in the heterozygote, where the highest increases were seen in the heart, was distinct from that in the hemizygote, where elevated levels of Gb3 and Ga2 were found in the kidney. Furthermore, the alpha-galactosidase activity in the heart, liver, and kidney of the heterozygote was 17%, 26%, and 36%, respectively, of normal controls, which correlated well with the accumulation of glycosphingolipid in the heart and with the disease's clinical manifestations. Two other hemizygotic patients, who were identified by low alpha-galactosidase activities, demonstrated the cardiac involvement. 相似文献
13.
Ken Sasaki Tohru Tanaka Yoshinori Nishizawa Mitsunori Hayashi 《Applied microbiology and biotechnology》1990,32(6):727-731
Summary For the production of a herbicide, 5-amino-levulinic acid (ALA), from anaerobic digestion liquor, the utilization of the photosynthetic bacterium, Rhodobacter sphaeroides was examined. This bacterium could produce ALA extracelularly from this liquor with the addition of levulinic acid (LA), an inhibitor of ALA dehydratase (ALAD), and glycine, a precursor of ALA biosynthesis in the Shemin pathway. Succinate (another precursor) addition was unnecessary for ALA production. When repeated additions of LA were made together with glycine ALA production was significantly enhanced. However, above three additions of LA, ALA production was not further enhanced. The maximum value of ALA production attained was 4.2 mM (0.63 g/ 1), which was over double that of other ALA producers such as Chlorella vulgaris. Propionic acid was predominantly utilized compared with other lower fatty acids, suggesting that this might be converted to ALA via succinyl-coenzyme A (CoA) in the methylmalonyl-CoA pathway.Offprint requests to: Y. Nishizawa 相似文献
14.
A new assay system for the detection of nicotianamine amino-transferase activity was developed. The activity of nicotianamine amino-transferase which participated in biosynthetic pathway of MAs from methionine in graminaceous plants was induced by the iron deficiency treatment. 相似文献
15.
Kazuko Wada Shintaro Nomura Eiichi Morii Yukihiko Kitamura Yasuko Nishizawa Akira Miyake Nobuyuki Terada 《The Journal of steroid biochemistry and molecular biology》1996,59(5-6):367-375
To examine the roles played by transforming growth factors (TGF)-β1, -β2, -β3, and TGF-β type II receptors in the induction of apoptosis in the mouse uterine epithelium after estrogen deprivation, we investigated the expression of their mRNAs and the mRNA of sulfated glycoprotein-2 (SGP-2). Pellets containing 100 μg estradiol-17β (E2) were implanted into ovariectomized mice and removed four days later. Apoptotic indices (percentage of apoptotic cells) of both luminal and glandular epithelia increased after E2 pellets were removed, but administration of progesterone (P), 5-dihydrotestosterone (DHT), or continued implantation of E2 pellets suppressed this increase. Levels of mRNAs of TGF-β1, -β2, and -β3, and SGP-2 did not increase after estrogen deprivation. However, estrogen deprivation caused a gradual increase in the level of TGF-β type II receptor mRNA, and its level increased about six-fold six days later. Moreover, E2, P, and DHT markedly decreased the level of TGF-β type II receptor mRNA. In situ hybridization demonstrated that mRNAs of TGF-β1, -β2, -β3 and TGF-β type II receptor were localized to the epithelium. Exogenous administration of TGF-β1 into the uterine stroma induced apoptosis in the epithelium, a finding that suggests that signals produced by TGF-βs can induce apoptosis. Therefore, the present results suggest that increased sensitivity of uterine epithelial cells to TGF-βs, as demonstrated by an increase in TGF-β type II receptor mRNA, is involved in the induction of apoptosis after estrogen deprivation, although signals produced by TGF-βs do not appear sufficient to induce apoptosis. 相似文献
16.
Koichiro Suzuki Kenji Kanazawa Kyoko Higuchi Naoko K. Nishizawa Satoshi Mori 《Biometals》1997,10(2):77-84
In a previous paper we reported that an acidic 36 kDa peptide is the most strongly induced peptide among several peptides induced by Fe deficiency in barley roots. In this paper, polyclonal antibodies were raised against the 36 kDa peptide. This peptide appeared in the roots of all the graminaceous species tested (barley, rye, wheat, oat, maize, sorghum and rice) in response to Fe deficiency. More of the peptide was found in the roots of graminaceous species which secrete higher amounts of mugineic acids (MAs) under Fe deficient nutrition status. Induction of the 36 kDa peptide was first observed on the third day of Fe deficiency, rising to a maximum value on the seventh day. The trend has a positive correlation with secretion of MAs during Fe deficiency. Further, resupply of Fe resulted in a decrease in peptide production on the second day, reaching a control level on the seventh day. The rate of decrease in peptide production was observed to be slower than that of MA secretion. Other nutrient stresses such as B excess, B deficiency, Cu excess, Cu deficiency, Mn excess, Mn deficiency, Zn excess and Zn deficiency induced far less of the peptide. The specific expression of the 36 kDa peptide in roots of graminaceous species under Fe deficiency suggested the positive association of the peptide with a specific Fe deficiency tolerance mechanism in graminaceous plants. 相似文献
17.
Miwako Nishizawa Kazushi Tanabe Taijo Takahashi 《Biochemical and biophysical research communications》1984,124(3):917-924
DNA topoisomerase activity together with the activities of DNA polymerase were detected in a form tightly associated with rat liver nuclear matrices. DNA polymerase activities were solubilized from the nuclear matrices of regenerating rat livers by sonic treatment followed by extraction of these activities with detergent and salt. The predominant activity was mainly α-polymerase as judged from the size determined by sucrose density gradient centrifugation. However, only β-polymerase activity was detected in the matrix of normal rat livers. DNA topoisomerase activity, detected in both regenerating and normal liver nuclear matrices, showed a molecular size of about 4 S in sucrose gradient, and was active in the presence of EDTA. These results suggest that this enzyme belongs to type I topoisomerase. 相似文献
18.
Cloning and nucleotide sequences of the linear DNA killer plasmids from yeast. 总被引:17,自引:11,他引:6
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F Hishinuma K Nakamura K Hirai R Nishizawa N Gunge T Maeda 《Nucleic acids research》1984,12(19):7581-7597
The linear DNA killer plasmids (pGKL1 and pGKL2) isolated from a Kluyveromyces lactis killer strain are also maintained and expressed its killer character in Saccharomyces cerevisiae. After these killer plasmid DNAs isolated from S. cerevisiae were treated with alkali, four terminal fragments from each plasmid DNAs were cloned separately. Using these and other cloned DNA fragments, the terminal nucleotide sequences of pGKL2 and the complete nucleotide sequence of pGKL1 were determined. The inverted terminal repetitions of 202 bp and 182 bp were found in pGKL1 and pGKL2, respectively. The pGKL1 sequence showed an extremely high A + T content of 73.2% and it contained five large open reading frames. The largest of these open reading frame was suggested to code for a membrane-bound precursor of glycoprotein subunit of the killer toxin. 相似文献
19.
Detection and mapping of six miniF-encoded proteins by cloning analysis of dissected miniF segments 总被引:11,自引:0,他引:11
Nobuhisa Komai Tsutomu Nishizawa Yasuhiko Hayakawa Tomoaki Murotsu Kenichi Matsubara 《Molecular & general genetics : MGG》1982,186(2):193-203
Summary Various DNA subfragments were derived from miniF DNA by complete or partial PstI cleavage, and cloned in the plasmid vectors pBR322 or dv1. The recombinant plasmids obtained were introduced into an Escherichia coli minicell-producing strain, and the plasmid-coded proteins were radiolabeled and analyzed by gel electrophoresis. Six miniF-encoded proteins, larger than 11 000 daltons, were detected and their coding regions were mapped on the F plasmid genome. Three of them were assigned by taking into account the known nucleotide sequences (Murotsu et al. 1981; K. Yoshioka, personal communication). The coding directions of some proteins were determined by inserting the lac promotor into one of the recombinant plasmids and analyzing the increase in production of the proteins. The coding direction of the five proteins analyzed so far was uniform. Comparison of these results with a functional map of miniF suggested possible roles of the proteins. 相似文献
20.
In situ growth of Neomysis intermedia Czerniawsky at the post-embryonicstage was studied by the cohort analysis using the probabilitygraphic technique in a hypereutrophic temperate lake, Lake Kasumigaura.Two overwintering populations and 5 spring cohorts were recognizedover 2-yr field observations performed at 415 day intervals.There was no luck in order to follow possible cohorts in mid-summerand autumn. The specific growth rate of the post-embryonic stagedetermined varied between 0.001 and 0.16 (day 1) dependingupon the surrounding water temperature, and each individualgrowth showed an almost exponential pattern. Average size ofnew born individuals was {small tilde}2.1 mm in body lengthand was consistent regardless of the difference of seasons,but the average mature size was highly temperature dependent,ranging between 7.6 and 12.0 mm for males and 8.1 and 13.5 mmfor females. 相似文献