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151.
Prenatal diagnosis for recessive dystrophic epidermolysis bullosa in 10 families by mutation and haplotype analysis in the type VII collagen gene (COL7A1). 总被引:1,自引:0,他引:1
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A. M. Christiano S. LaForgia A. S. Paller J. McGuire H. Shimizu J. Uitto 《Molecular medicine (Cambridge, Mass.)》1996,2(1):59-76
BACKGROUND: Epidermolysis bullosa (EB) is a group of heritable diseases that manifest as blistering and erosions of the skin and mucous membranes. In the dystrophic forms of EB (DEB), the diagnostic hallmark is abnormalities in the anchoring fibrils, attachment structures beneath the cutaneous basement membrane zone. The major component of anchoring fibrils is type VII collagen, and DEB has been linked to the type VII collagen gene (COL7A1) at 3p21, with no evidence for locus heterogeneity. Due to life-threatening complications and significant long-term morbidity associated with the severe, mutilating form of recessive dystrophic EB (RDEB), there has been a demand for prenatal diagnosis from families with affected offspring. MATERIALS AND METHODS: Intragenic polymorphisms in COL7A1 and flanking microsatellite markers on chromosome 3p21, as well as detection of pathogenetic mutations in families, were used to perform PCR-based prenatal diagnosis from DNA obtained by chorionic villus sampling at 10-15 weeks or amniocentesis at 12-15 weeks gestation in 10 families at risk for recurrence of RDEB. RESULTS: In nine cases, the fetus was predicted to be normal or a clinically unaffected carrier of a mutation in one allele. These predictions have been validated in nine cases by the birth of a healthy child. In one case, an affected fetus was predicted, and the diagnosis was confirmed by fetal skin biopsy. CONCLUSIONS: DNA-based prenatal diagnosis of RDEB offers an early, expedient method of testing which will largely replace the previously available invasive fetal skin biopsy at 18-20 weeks gestation. 相似文献
152.
Mayumi Shimizu Kazunari Inaba Toyokazu Yoshida Takayoshi Toda Akio Iwashima Toshio Mitsunaga 《Physiologia plantarum》1995,93(1):93-98
Three thiamine-binding proteins of 17-19 kDa (STBP-I, II, and III) were purified from sesame seed (Sesamum indicum L.). Each of the proteins was composed of two subunits of equal molecular mass and each subunit consisted of a large polypeptide and a small polypeptide linked by a disulfide bond(s). They were rich in glutamic acid (or glutamine) and arginine. Their binding activities were optimal at neutral pH. They bound specifically free thiamine but not thiamine phosphates. STBP-I had higher affinity for thiamine than STBP-II or STBP-III. STBP-II and STBP-III bound one molecule of thiamine per molecule, and STBP-I bound 0.5 molecule. The amino acid composition and structure of the STPBs were similar to those of 2S storage proteins. 相似文献
153.
Shimizu Tsutomu; Hashimoto Naoya; Nakayama Ishizue; Nakao Tohru; Mizutani Hiroyuki; Unai Tadaaki; Yamaguchi Mikio; Abe Hiroshi 《Plant & cell physiology》1995,36(4):625-632
A novel isourazole herbicide, fluthiacet-methyl (methyl [[2-chloro-4-fluoro-5-[(5,6,7,8-tetrahydro-3-oxo-lH,3H-[l,3,4]thiadiazolo[3,4-a]pyridazin-l-ylidene)amino]phenyrjthio]acetate;experimental code name, KIH-9201) promoted the leakage of electrolytesfrom cotyledons of velvetleaf (Abtilon theophtasti Medic) andcotton (Gossypium hirsutum L.) plants that are sensitive tothis compound. It induced the accumulation of protoporphyrinIX in cotyledons of cotton and inhibited Chl biosynthesis incotyledons of velvetleaf and cotton at low concentrations (I50values, 1012 nM). Fluthiacet-methyl was converted toits urazole by glutathione S-transferase that had been partiallypurified from velvetleaf. The urazole inhibited protoporphyrinogenoxidase (Protox, EC 1.3.3.4
[EC]
) from some plants, including velvetleaf,at low concentrations (I50 values, 5.111 nM), whereasfluthiacet-methyl was not as potent. The effects in vivo (electrolyteleakage and inhibition of Chi biosynthesis) of fluthiacet-methylwere correlated with the inhibition of Protox activity by theurazole and not with the action of fluthiacet-methyl itself.From these results, it is concluded that fluthiacet-methyl inhibitsProtox activity after conversion to the corresponding urazoleby glutathione S-transferase. It is in this way that fluthiacet-methylexerts its effect as a light-dependent peroxidizing herbicide. (Received November 1, 1994; Accepted March 6, 1995) 相似文献
154.
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156.
The physiological states with respect to cell growth and ethanol production in a yeast fed-batch culture expressed in linguistic form could be recognized on-line by fuzzy inferencing based on error vectors. The error vector was newly defined here in a macroscopic elemental balance equation. The physiological states for cell growth and ethanol production were characterized by error vectors using many experimental data from fed-batch cultures. Fuzzy membership functions were constructed from the frequency distributions of the error vectors and state recognition was performed by fuzzy inferencing. In particular, an unusual physiological state for a yeast cultivation, in which aerobic ethanol production was accompanied by very low cell growth, could be recognized accurately. According to the results of the state recognition, an energy parameter, the P/O ratio in the metabolic reaction model was adaptively estimated, and the cell growth was successfully evaluated with the estimated P/O. (c) 1995 John Wiley & Sons, Inc. 相似文献
157.
M Shimizu E Ichikawa U Inoue T Nakamura T Nakajima H Nojima H Okayama K Oda 《Molecular and cellular biology》1995,15(5):2882-2892
158.
Akira Uchimura Toshiyuki Shimizu Masahiro Morita Hitomi Ueno Kazuhiro Motoki Hideaki Fukushima Takenori Natori Yasuhiko Koezuka 《Bioorganic & medicinal chemistry》1997,5(12):2245-2249
We compared the immunostimulatory effects of chemically synthesized α-galactosylceramides (α-GalCers), α-glucosylceramides (α-GluCers), 6″-monoglycosylated α-GalCer and 6″- or 4″-monoglycosylated α-GluCer and made the following observations: (1) the length of the fatty acid side chain in the ceramide portions greatly affects the immunostimulatory effects of α-GalCers and α-GluCers; (2) the configuration of the 4″-hydroxyl group of the inner pyranose moiety plays an important role in the immunostimulatory effects of monoglycosylated α-
-pyranosylceramides; (3) the free 4″-hydroxyl group of the inner pyranose of monoglycosylated α-
-pyranosylceramides plays a more important role in their immunostimulatory effects than the free 6″-hydroxyl group. 相似文献
159.
Understanding of factors influencing settlement(attachment and metamorphosis) of marine invertebratelarvae is of great importance in aquaculture andcontrol of biofouling. The influence of two factors onsettlement of larvae was assessed from two separateinvestigations: 1, the influence of age (endogenousfactor) on cyprids of the barnacle Balanusamphitrite; and 2, the influence of a microbial film(exogenous factor) on pediveligers of the mussel Mytilus galloprovincialis.The settlement response of cypris larvae of B.amphitrite was found to be age-dependent. Oldercyprids responded more readily to settlement factorsthan newly molted ones. In M.galloprovincialis, competent pediveligers settled inresponse to a microbial filmed surface but not toan unfilmed surface. Moreover, a factor with MW of lessthan 5000 dalton, derived from culture medium of abacterial strain C1.1 (Pseudomonas-Alteromonasgroup), induced the settlement of M. galloprovincialis larvae.Thus, marine invertebrate larvae may require a periodof competence acquisition, during which they arepoorly responsive to settlement inducers. Uponacquisition of competence, larvae readily respondto external cues (e.g. microbial film, bacterialextracellular products). 相似文献
160.
Physical effects of negative air ions in a wet sauna 总被引:10,自引:0,他引:10
I. Watanabe Hiroshi Noro Yoshinori Ohtsuka Yukio Mano Yuko Agishi 《International journal of biometeorology》1997,40(2):107-112
The physical effects of negative air ions on humans were determined in an experimental sauna room equipped with an ionizer.
Thirteen healthy persons took a wet sauna bath (dry bulb temperature 42° C, relative humidity 100%, 10 min exposure) with
or without negative air ions. The subjects were not told when they were being exposed to negative air ions. There were no
differences in the moods of these persons or changes in their blood pressures between the two saunas. The surface temperatures
of the foreheads, hands, and legs in the sauna with negative ions were significantly higher than those in the sauna without
ions. The pulse rates and sweat produced in the sauna with ions were singificantly higher than those in the sauna without
ions. The results suggest that negative ions may amplify the effects on humans of the sauna.
Received: 31 March 1995 / Revised: 25 July 1995 / Accepted: 26 July 1996 相似文献