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991.
Production of bioactive triterpenes by Eriobotrya japonica calli 总被引:8,自引:0,他引:8
Taniguchi S Imayoshi Y Kobayashi E Takamatsu Y Ito H Hatano T Sakagami H Tokuda H Nishino H Sugita D Shimura S Yoshida T 《Phytochemistry》2002,59(3):315-323
Callus tissue cultures induced from an axenic leaf of Eriobotrya japonica (Rosaceae) produced triterpenes in large amounts (ca. 50 mg/g dry wt). Nine triterpenes were characterized as ursolic acid, oleanolic acid, 2alpha-hydoxyursolic acid, maslinic acid, tormentic acid, 2alpha, 19alpha-dihydroxy-3-oxo-urs-12-en-28-oic acid, hyptadienic acid and a mixture of 3-O-cis-p-coumaroyltormentic acid and 3-O-trans-p-coumaroyltormentic acid. The triterpene composition in the callus tissues was noticeably different from that in intact leaves. The contents of tormentic acid with antidiabetic action, and 2alpha, 19alpha-dihydroxy-3-oxo-urs-12-en-28-oic acid with anti-HIV activity, were much larger than those in the intact leaves. All of the triterpenes isolated from the callus tissues showed an inhibitory effect comparable to (-)-epigallocatechin gallate (EGCG) of green tea on the activation of Epstein-Barr virus early antigen (EBV-EA) induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). 2alpha, 19alpha-Dihydroxy-3-oxo-urs-12-en-28-oic acid was the most potent inhibitor among them and caused a significant delay of two-stage carcinogenesis on mouse skin. 相似文献
992.
Shiraishi K Shimura T Taga M Uematsu N Gondo Y Ohtaki M Kominami R Niwa O 《Radiation research》2002,157(6):661-667
Untargeted mutation and delayed mutation are features of radiation-induced genomic instability and have been studied extensively in tissue culture cells. The mouse pink-eyed unstable (p(un)) mutation is due to an intragenic duplication of the pink-eyed dilution locus and frequently reverts back to the wild type in germ cells as well as in somatic cells. The reversion event can be detected in the retinal pigment epithelium as a cluster of pigmented cells (eye spot). We have investigated the reversion p(um) in F1 mice born to irradiated males. Spermatogonia-stage irradiation did not affect the frequency of the reversion in F1 mice. However, 6 Gy irradiation at the spermatozoa stage resulted in an approximately twofold increase in the number of eye spots in the retinal pigment epithelium of F1 mice. Somatic reversion occurred for the paternally derived p(un) alleles. In addition, the reversion also occurred for the maternally derived, unirradiated p(un) alleles at a frequency equal to that for the paternally derived allele. Detailed analyses of the number of pigmented cells per eye spot indicated that the frequency of reversion was persistently elevated during the proliferation cycle of the cells in the retinal pigment epithelium when the male parents were irradiated at the spermatozoa stage. The present study demonstrates the presence of a long-lasting memory of DNA damage and the persistent up-regulation of recombinogenic activity in the retinal pigment epithelium of the developing fetus. 相似文献
993.
Fujita H Kosaki R Yoshihashi H Ogata T Tomita M Hasegawa T Takahashi T Matsuo N Kosaki K 《Teratology》2002,65(1):10-18
BACKGROUND: Genetic background of a fetus contributes to the abnormal development after teratogen exposure. In rodents, in utero exposure to dioxins affects male external genital development. The effects of dioxins are mediated via the aryl hydrocarbon receptor (AHR) and its binding protein, aryl hydrocarbon receptor nuclear translocator (ARNT). In mice, aryl hydrocarbon receptor repressor (AHRR), which binds to ARNT in competition with AHR, plays a critical negative regulatory role in AHR signaling. We attempt to characterize the human AHRR gene and investigate the relationship between AHRR polymorphisms and the incidence of micropenis, a phenotype of undermasculinization. METHODS: We identified and characterized the human homolog of mouse AHRR, taking advantage of the publicly available draft version of the human genome sequence. After detecting an AHRR protein polymorphism by the direct sequencing of pooled human genomic DNA, we evaluated the association between the polymorphism and the presence or absence of micropenis (< -2.5 SD) in patients with micropenis and control subjects. RESULTS: The deduced sequence for human AHRR (715 residues) and the mouse AHRR protein exhibited 81% sequence homology to each other. The Pro185Ala polymorphism was identified between the PAS-A region and the highly conserved arginine/cysteine-rich RCFRCRL/VRC region. Forty-six percent (27/59) of patients with micropenis and 27% (22/80) of the controls were homozygous for 185Pro; this difference in frequencies was significant (P = 0.03). CONCLUSIONS: Homozygosity for the 185Pro allele of AHRR may increase the susceptibility of a fetus to the undermasculinizing effects of dioxin exposure in utero, presumably through the diminished inhibition of AHR-mediated signaling. 相似文献
994.
Shirotani-Ikejima H Kokame K Hamuro T Bu G Kato H Miyata T 《Biochemical and biophysical research communications》2002,299(5):847-852
Tissue factor pathway inhibitor (TFPI) is a Kunitz-type protease inhibitor that regulates tissue factor-triggered blood coagulation. It has previously been reported that TFPI inhibits the proliferation of human umbilical vein endothelial cells (HUVECs), suggesting that TFPI may act as more than just a mediator of coagulation through changes in gene expression. By using DNA-array techniques and Northern blot analysis, we here revealed that TFPI transiently induced the mRNA expression of JUNB and GADD45B. The inducible effects were not observed in TFPIdeltaC (lacking the C-terminal basic region) or antithrombin (heparin-binding anticoagulant protease inhibitor). Moreover, the TFPI-induced expression of GADD45B was blocked by receptor-associated protein, which masks the ligand-binding domain of very low density lipoprotein receptor (VLDL-R). In conclusion, this is the first report to show an effect of TFPI on mRNA expression, and suggests that TFPI modulates cellular functions by inducing JUNB and GADD45B expression through binding to VLDL-R. 相似文献
995.
Kashima K Nagahama J Sato K Tanamachi H Gamachi A Daa T Nakayama I Yokoyama S 《Acta cytologica》2002,46(4):709-712
OBJECTIVE: To apply the polymerase chain reaction (PCR) for detection of the HTLV-I gene from cytologic smear slides. STUDY DESIGN: Samples were from seven cases of serum anti-ATL antibody (ATLA)-positive T-cell lymphoma and three from ATLA-negative T-cell lymphoma. Six of the seven ATLA-positive cases were confirmed to be ATLL by Southern blotting. From the seventh case a fresh sample for blotting could not obtained. DNA was extracted from the cytologic smear slides of all 10 cases; they had been stained with Papanicolaou or May-Giemsa stain, digested with proteinase K and precipitated with phenol and ethanol. The target sequence in the pX region of the HTLV-I gene was amplified by PCR. RESULTS: All seven ATLA-positive cases, including one that had not yet been confirmed by Southern blotting, showed a single band, as predicted, while the three ATLA-negative cases showed no band. CONCLUSION: If cytologic smear slides are available but a fresh sample is not, the PCR method should provide evidence that the virus is present since in our study sufficient DNA templates were successfully extracted from the stained cytologic smear slides for detection of the virus. 相似文献
996.
Kimura H Ogura T Kurashima Y Weisz A Esumi H 《Biochemical and biophysical research communications》2002,296(4):976-982
Nitric oxide (NO) has been reported to modulate the vascular endothelial growth factor (VEGF) gene by accumulating hypoxia-inducible factor-1alpha (HIF-1alpha) protein, but there is a contradiction among effects of various NO donors. The effects of NO donors including S-nitroso-N-acetyl-penicillamine (SNAP), S-nitroso-glutathione (GSNO), 1-hydroxy-2-oxo-3,3-bis(2-aminoethyl)-1-triazene (NOC18), 3-[(+/-)-(E)-ethyl-2(')-[(E)-hydroxyimino]-5-nitro-3-hexenecarbamoyl]-pyridine (NOR4), 3-morpholinosydnonimine (SIN-1), and nitroprusside (SNP) on the VEGF reporter gene were examined. SNAP, GSNO, NOC18, and NOR4 enhanced the VEGF reporter activity under normoxia and modulated the hypoxic induction. In contrast, SNP had only an inhibitory effect. An NO scavenger attenuated the reporter activation by NO donors except NOR4, but did not ameliorate the inhibitory effect of SNP. A reducing compound dithiothreitol suppressed NO-induced activation of the VEGF reporter gene. SNAP, GSNO, and NOC18 induced the accumulation of HIF-1alpha protein, while others did not. These results suggest that SNAP, GSNO, and NOC compounds are suitable for pharmacological studies in HIF-1-mediated VEGF gene activation by NO. 相似文献
997.
Simple synthesis of sialyllactose-carrying polystyrene and its binding with influenza virus 总被引:4,自引:0,他引:4
Akiko Tsuchida Kazukiyo Kobayashi Noritaka Matsubara Tsukasa Muramatsu Takashi Suzuki Yasuo Suzuki 《Glycoconjugate journal》1998,15(11):1047-1054
Glycoconjugate polystyrenes bearing sialyllactose moieties were prepared via a simple method from a mixture of 2-6 and 2-3 linked sialyllactose isomers of bovine milk origin. The reducing end of sialyllactose was converted to an amino function with ammonium hydrogen carbonate and then coupled with p -vinylbenzoyl chloride. The resulting styrene derivative substituted with sialyllactose via an amide linkage was polymerized with ammonium peroxodisulfate and N,N,N,N -tetramethylethylenediamine in water at 30 °C. The interaction of the glycopolymer with influenza A and B viruses was investigated by three different methods. The glycopolymer inhibited the hemagglutination of influenza A virus (PR/8/34) and its activity was 103 times higher than that of the oligosaccharide itself. The cytopathic effect of virus-infected MDCK (Madine-Darby canine kidney) cells was inhibited by the glycopolymer. The homopolymer showed 102 times higher inhibitory activity than naturally-occurring fetuin. It was also found that various viruses could be trapped by the glycopolymer adsorbed on a polystyrene surface. The inhibitory and trapping activities of the glycopolymers were correlated with the sialyl linkage specificities of the virus strains. 相似文献
998.
999.
1000.
R. Matsuoka Misa Kimura Peter J. Scambler Bernice E. Morrow Shin-ichiro Imamura Shinsei Minoshima Nobuyoshi Shimizu Hiroyuki Yamagishi Kunitaka Joh-o Seiichi Watanabe Kotaro Oyama Tsutomu Saji Masahiko Ando Atsuyoshi Takao Kazuo Momma 《Human genetics》1998,103(1):70-80
To investigate molecular and clinical aspects of conotruncal anomaly face (CAF), we studied the correlation between deletion
size and phenotype and the mode of inheritance in 183 conotruncal anomaly face syndrome (CAFS) patients. Hemizygosity for
a region of 22q11.2 was found in 180 (98%) of the patients with CAFS by fluorescence in situ hybridization (FISH) using the
N25(D22S75) DiGeorge critical region (DGCR) probe. No hemizygosity was found in three (2%) of the patients with CAFS by FISH
using nine DiGeorge critical region probes and a SD10P1 probe (DGA II locus). None of these three patients had mental retardation
and just one had nasal intonation, which was observed in almost all of the 180 CAFS patients who carried deletions (mental
retardation, 92%; nasal voice, 88%). Nineteen of 143 families (13%) had familial CAFS and 16 affected parents (84%) were mothers.
Although only two of the affected parents had cardiovascular anomalies, the deletion size in the 16 affected parents and their
affected family members, who were studied by FISH analysis, was the same. It indicates that extragenic factors may play a
role in the genesis of phenotypic variability, especially in patients with cardiovascular anomalies. No familial cases were
found among CAFS patients with absent thymus/DiGeorge anomaly (DGA). Also, in all 18 CAFS patients with completely absent
thymus/DGA and all 6 CAFS patients with schizophrenia, it was revealed that the deletion was longer distally. A study of the
origin of the deletion using microsatellite analyses in 48 de novo patients showed that in 65% of CAFS patients it was maternal,
while in 64% of DGA patients it was paternal. The findings of this study indicated that CAF was almost always associated with
the deletion of 22q11.2. As well as the major features of the syndrome, other notable extracardiac anomalies were found to
be susceptibility to infection, schizophrenia, atrophy or dysmorphism of the brain, thrombocytopenia, short stature, facial
palsy, anal atresia, and mild limb abnormalities.
Received: 5 January 1998 / Accepted: 7 March 1998 相似文献