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101.
Chung HS Um JY Kim MS Hong SH Kim SM Kim HK Park SJ Kim SC Hwang WJ Kim HM 《Hereditas》2002,136(2):126-129
Analyses of randomly amplified polymorphic DNA (RAPD) and PCR-restriction fragment length polymorphism (PCR-RFLP) were performed in an effort to distinguish between two different origins of Pinellia ternata. To determine whether the origin of Pinellia ternata is in China or Korea. RAPD analysis was carried out using ten 20-mer random primers. Although the coefficients of similarity between the DNA of Chinese and Korean accessions of Pinellia ternata were high, distinguishable band patterns were observed in the reaction performed using primer numbers 3, 6 and 10. Primer 3 produced one (410 bp) and primer 6 produced four (410 bp, 350 bp, 300 bp, 250 bp) Chinese Pinellia-specific fragments. Primer 10 produced one (900 bp) Korean Pinellia rhizome-specific fragment. In addition, using PCR-RFLP analysis, different fingerprints were obtained from Korean and Chinese Pinellia ternata respectively. These results suggest that the analyses with RAPD and PCR-RFLP can be used to authenticate the relevant Chinese and Korean herbal medicines. 相似文献
102.
103.
OBJECTIVE: To investigate estrogen receptor (ER) and progesterone receptor (PR) levels in imprint specimens obtained at breast surgery and to compare their correlation with that of standard methods. STUDY DESIGN: Imprint specimens for cytology were obtained from 101 mass-forming lesions in 66 patients, and specimens were frozen in liquid nitrogen for later assay. The imprint specimens were immunocytochemically (ICC) stained by monoclonal antibody to ER or PR; diaminobenzidine-stained cell nuclei in clusters were regarded as positive. Tissue specimens were assayed by the standard method of dextran-coated charcoal assay (DCC) and enzyme immunoassay. RESULTS: Forty-five primary breast cancer lesions, 2 contralateral breast cancer, 49 dissected nodes and 5 benign breast lesions were collected. The correlation between DCC and ICC was 81% (82/101) for ER and 74% (66/101) for PR. That between EIA and ICC was 88% (88/99) for ER and 80% (79/100) for PR, higher than that between DCC and ICC for ER and PR. CONCLUSION: ICC assessment of ER or PR on imprint cytology is a promising clinical test with an acceptable correlation. 相似文献
104.
Uchiro H Nagasawa K Kotake T Hasegawa D Tomita A Kobayashi S 《Bioorganic & medicinal chemistry letters》2002,12(20):2821-2824
The first synthesis of 9-methoxystrobilurin-type beta-substituted MOAs was successfully achieved. A chiral oudemansin-type beta-substituted MOA was also synthesized utilizing Mukaiyama's asymmetric aldol reaction. Antifungal activities of the synthesized compounds against several representative fungi were examined by disk-diffusion assay. As a result, unique and superior antifungal properties of 9-methoxystrobilurin-type beta-substituted MOAs compared with those of oudemansin-type analogue were clearly revealed. 相似文献
105.
Biros E Kalina I Kohút A Bogyiová E Salagovic J Sulla I 《Physiological research / Academia Scientiarum Bohemoslovaca》2002,51(1):59-64
The polymorphisms of the tumor suppressor gene p53 in exon 4 (p53 BstUI) and in intron 6 (p53 MspI) have been suggested to be associated with the genetically determined susceptibility in diverse types of human cancer. In our hospital-based case-control study, we examined the allele and genotype incidence of these polymorphisms as well as their haplotype combinations in 60 brain tumor patients (27 males and 33 females) and 183 controls without malignancies. The genotype characteristics were determined by the PCR-based RFLP method using DNA extracted from peripheral blood. In this study we show that the p53 BstUI and the p53 MspI polymorphisms are not associated with increased risk of brain tumors. Thus, we conclude that the p53 BstUI and the p53 MspI polymorphic sites within the tumor suppressor gene p53 do not represent genetic determinants of susceptibility to brain tumors. 相似文献
106.
Yamamoto K Shibata F Miyasaka N Miura O 《Biochemical and biophysical research communications》2002,297(5):1245-1252
IL-12 activates STAT4 by inducing tyrosine phosphorylation, homo-dimerization, and nuclear translocation in NK cells and thereby stimulates proliferation and activation of these cells. The pore-forming protein perforin is a key effector protein for NK cell- and cytotoxic T lymphocyte-mediated cytolysis. Here we demonstrate that IL-12 induces the expression of the perforin gene in human NK cell line, NKL. Electrophoretic mobility shift assays using a probe containing two putative STAT-binding sequences located at -1085 and -1059 in the human perforin gene showed that STAT4 or STAT5 activated by IL-12 or IL-2, respectively, in NKL cells binds this region. Further analyses using various probes with or without mutated STAT-binding sequences showed that, although either of the two tandem STAT-binding sequences binds STAT4 weakly, the presence of both is required for significant binding of activated STAT4 and for formation of the STAT4-DNA-binding complex with lower electrophoretic mobility. Furthermore, mutation of either of the tandem STAT-binding sequences abolished the IL-12-induced activation of the perforin gene promoter in reporter gene assays. These results indicate that the IL-12-induced expression of the perforin gene in NK cells is directly regulated by STAT4, which binds, most likely as a homo-tetramer, to the tandem STAT-binding sequences in the perforin gene promoter. 相似文献
107.
Goh YL Yasin R Puthucheary SD Koh YT Lim VK Taib Z Thong KL 《Journal of applied microbiology》2003,95(5):1134-1142
AIMS: DNA fingerprinting of Salmonella enterica serotype Paratyphi B isolated in Malaysia during 1982-83, 1992 and 1996-2002 was carried out by pulsed-field gel electrophoresis (PFGE), antimicrobial susceptibility tests and D-tartrate utilization tests to assess the extent of genetic diversity of these isolates in Malaysia. METHODS AND RESULTS: Eighty-six human isolates and one food isolate of Salm. Paratyphi B were analysed by PFGE, antimicrobial susceptibility tests and D-tartrate utilization tests. Sixty-five strains were D-tartrate-negative (dT-) while 22 strains were D-tartrate-positive (dT+). Thirty-seven per cent of the Salm. Paratyphi B strains were resistant to one or more antimicrobial agents. PFGE analysis clearly distinguished the dT- and dT+ strains into two clusters based on the unweighted pair group average method (UPGMA). Twenty-two XbaI-pulsotypes were observed among the 65 dT- strains while 17 XbaI-pulsotypes were observed among the 22 isolates of Salm. Paratyphi B dT+. CONCLUSIONS: The present study showed that PFGE was very discriminative with 33.7% of the strains yielding distinct fingerprints. Paratyphoid fever in Malaysia is probably caused by one predominant, endemic clone of Salm. Paratyphi B dT- with various subtypes. There was no association between the pulsotypes and the severity of the disease indicating that the severity of the disease is probably multifactorial. SIGNIFICANCE AND IMPACT OF THE STUDY: The findings of the present study verify the usefulness of PFGE in characterizing strains of Salm. Paratyphi B. This is the first report on the application of PFGE on a large collection of Salm. Paratyphi B in Malaysia. 相似文献
108.
Hot-water extract from mycelia of Cordyceps sinensis as a substitute for antibiotic growth promoters 总被引:2,自引:0,他引:2
Broiler chicks were orally dosed with a hot-water extract of mycelia from Cordyceps sinensis (CS-HW) to assess possible substitution of Avilamycin as an antibiotic growth promoter (AGP). The growth performance (body weight gain and survivability) and the health index (the microflora in the small intestines and the antibody titer to Newcastle disease virus) of chicks were significantly improved in the CS-HW (600 mg/kg diet) and the Avilamycin (20 mg/kg diet) fed group in comparison with the control group (p<0.05). The Avilamycin-fed group and the CS-HW-fed group had similar growth performances but the latter gave a better microbial flora in the small intestines. These results indicate that CS-HW enhances the physiological activity in chicks and can be used as a substitute for AGPs. 相似文献
109.
The ion-exchange chromatography behavior of recombinant glucose dehydrogenase harboring pyrroloquinoline quinone (PQQGDH) was modified to greatly simplify its purification. The surface charge of PQQGDH was engineered by either fusing a three-arginine tail to the C-terminus of PQQGDH (PQQGDH+Arg3) or by substituting three residues exposed on the surface of the enzyme to Arg by site-directed mutagenesis (3RPQQGDH). During cation exchange chromatography, both surface charge-engineered enzymes eluted at much higher salt concentrations than the wild-type enzyme. After the chromatography purification step, both PQQGDH+Arg3 and 3RPQQGDH appeared as single bands on SDS-PAGE, while extra bands appeared with the wild-type protein sample. Although all tested kinetic parameters of both engineered enzymes are similar to those of wild type, both modifications resulted in enzymes with increased thermal stability. Our achievements have resulted in the greater production of an improved quality PQQGDH by a simplified process. 相似文献
110.