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911.
Rapid and simple method for DNA extraction from plant and algal species suitable for PCR amplification using a chelating resin Chelex 100 总被引:1,自引:0,他引:1
Kwon HwangBo Su Hyun Son Jong Suk Lee Sung Ran Min Suk Min Ko Jang R. Liu Dongsu Choi Won Joong Jeong 《Plant biotechnology reports》2010,4(1):49-52
A DNA extraction method using Chelex 100 is widely used for bacteria, Chlamydomonas, and animal cell lines, but only rarely for plant materials due to the need for additional time-consuming and tedious steps.
We have modified the Chelex 100 protocol and successfully developed a rapid and simple method of DNA extraction for efficient
PCR-based detection of transgenes from a variety of transgenic plant and algal species. Our protocol consists of homogenizing
plant tissue with a pestle, boiling the homogenized tissue in a microfuge tube with 5% Chelex 100 for 5 min, and centrifuging
the boiled mixture. The supernatant, which is used for PCR analysis, was able to successfully amplify transgenes in transgenic
tobacco, tomato, potato, Arabidopsis, rice, strawberry, Spirodela polyrhiza, Chlamydomonas, and Porphyra tenera. The entire DNA extraction procedure requires <15 min and is therefore comparable to that used for bacteria, Chlamydomonas, and animal cell lines. 相似文献
912.
Arnousse Beaulière Siaka Touré Pierre-Kébreau Alexandre Koko Koné Alex Pouhé Bertin Kouadio Neige Journy Jér?me Son Virginie Ettiègne-Traoré Fran?ois Dabis Serge Eholié Xavier Anglaret 《PloS one》2010,5(6)
Background
Large HIV care programs frequently subsidize antiretroviral (ARV) drugs and CD4 tests, but patients must often pay for other health-related drugs and services. We estimated the financial burden of health care for households with HIV-infected adults taking antiretroviral therapy (ART) in Côte d''Ivoire.Methodology/Principal Findings
We conducted a cross-sectional survey. After obtaining informed consent, we interviewed HIV-infected adults taking ART who had consecutively attended one of 18 HIV care facilities in Abidjan. We collected information on socioeconomic and medical characteristics. The main economic indicators were household capacity-to-pay (overall expenses minus food expenses), and health care expenditures. The primary outcome was the percentage of households confronted with catastrophic health expenditures (health expenditures were defined as catastrophic if they were greater than or equal to 40% of the capacity-to-pay). We recruited 1,190 adults. Median CD4 count was 187/mm3, median time on ART was 14 months, and 72% of subjects were women. Mean household capacity-to-pay was $213.7/month, mean health expenditures were $24.3/month, and 12.3% of households faced catastrophic health expenditures. Of the health expenditures, 75.3% were for the study subject (ARV drugs and CD4 tests, 24.6%; morbidity events diagnosis and treatment, 50.1%; transportation to HIV care centres, 25.3%) and 24.7% were for other household members. When we stratified by most recent CD4 count, morbidity events related expenses were significantly lower when subjects had higher CD4 counts.Conclusions/Significance
Many households in Côte d''Ivoire face catastrophic health expenditures that are not attributable to ARV drugs or routine follow-up tests. Innovative schemes should be developed to help HIV-infected patients on ART face the cost of morbidity events. 相似文献913.
Jae-Han Son Kyong-Cheul Park Tae-Won Kim Young-Jin Park Jung-Hoon Kang Nam-Soo Kim 《Genes & genomics.》2010,32(2):165-172
Allium is a very diverse genus with over 600 species distributed worldwide. Haplotype analyses of 45S rRNA ITS, trnH-psbA spacer, and matK gene sequences in 9 Allium species were carried out, subsequent to which phylogenetic relations of the nine species were also analyzed. Of the three genes, the nuclear 45S rRNA ITS sequences showed the highest variation with one haplotype in each species. The other two chloroplast genes revealed that more than one haplotype was present in each species, and each haplotype was present in several of the species. In the matK gene, EcoRI restriction revealed heteroplasmy in which the functional gene retains the EcoRI recognition site while the nonfunctional, pseudogene does not. Phylogenetic patterns were not consistent among the haplotypes of the 45 rRNA ITS, trnH-psbA spacer, and matK genic regions. This phylogenetic incongruency might be due to the presence of multiple haplotypes in each of the chloroplast genes. However, the inconsistency of the phylogenetic relationships, based on the 45S rRNA ITS sequences makes a strong case for further analysis. 相似文献
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917.
Nari Jeong Seong-Cheol Park Ramamourthy Gopal Byoung Kwan Son Yoonkyung Park Kyung-Soo Hahm 《Biochemical and biophysical research communications》2010,399(4):581-586
Pseudomonas aeruginosa has eventually developed resistance against flomoxef sodium, isepamicin and cefpiramide. Therefore, in this study, the antibacterial activity and synergistic effects of the amphipathic-derived P5-18mer antimicrobial peptide were tested against pathogens associated with cholelithiasis that have developed resistance against commonly used antibiotics. The results were then compared with the activities of the amphipathic-derived peptide, P5-18mer, melittin and common antibiotics. Growth inhibition of planktonic bacteria was tested using the National Committee for Clinical Laboratory Standards (NCCLS). The bactericidal activity of the antimicrobial peptides was measured using time-kill curves. Synergistic effects were evaluated by testing the effects of P5-18mer alone and in combination with flomoxef sodium, isepamicin or cefpiramide at 0.5 × MIC. P5-18mer peptide displayed strong activity against pathogens and flomoxef sodium, isepamicin and cefpiramide-resistant bacteria cell lines obtained from a patient with gallstones; however, it did not exert cytotoxicity against the human keratinocyte HaCat cell line. In addition, the results of time-kill curves indicated that P5-18mer peptide exerted bactericidal activity against four strains of P. aeruginosa. Finally, the use of P5-18mer and antibiotics exerted synergistic effects against cell lines that were resistant to commonly used antibiotics. These results indicate that this class of peptides has a rapid microbicidal effect on flomoxef sodium, isepamicin and cefpiramide-resistant strains of P. aeruginosa. Therefore, these peptides may be used as a lead drug for the treatment of acquired pathogens from patients with cholelithiasis who are affected with antibiotic-resistant bacteria. 相似文献
918.
Crystal structure of the catalytic domain of human MAP kinase phosphatase 5: structural insight into constitutively active phosphatase 总被引:1,自引:0,他引:1
Jeong DG Yoon TS Kim JH Shim MY Jung SK Son JH Ryu SE Kim SJ 《Journal of molecular biology》2006,360(5):946-955
MAP kinase phosphatase 5 (MKP5) is a member of the mitogen-activated protein kinase phosphatase (MKP) family and selectively dephosphorylates JNK and p38. We have determined the crystal structure of the catalytic domain of human MKP5 (MKP5-C) to 1.6 A. In previously reported MKP-C structures, the residues that constitute the active site are seriously deviated from the active conformation of protein tyrosine phosphatases (PTPs), which are accompanied by low catalytic activity. High activities of MKPs are achieved by binding their cognate substrates, representing substrate-induced activation. However, the MKP5-C structure adopts an active conformation of PTP even in the absence of its substrate binding, which is consistent with the previous results that MKP5 solely possesses the intrinsic activity. Further, we identify a sequence motif common to the members of MKPs having low catalytic activity by comparing structures and sequences of other MKPs. Our structural information provides an explanation of constitutive activity of MKP5 as well as the structural insight into substrate-induced activation occurred in other MKPs. 相似文献
919.
Park MH Lee SM Lee JW Son DJ Moon DC Yoon DY Hong JT 《Biochemical and biophysical research communications》2006,339(4):1021-1028
Erythropoietin (EPO), a hematopoietic factor, is also required for normal brain development, and its receptor is localized in brain. Our previous study showed that EPO promotes differentiation of neuronal stem cells into astrocytes. Since astrocytes have influence on the neuronal function, we investigated whether EPO-activated astrocytes could stimulate differentiation of neuronal stem cells into neurons. EPO did not promote neuronal differentiation of neuronal stem cells isolated from 17 day embryos, however, neuronal differentiation was promoted when the neuronal stem cells were co-cultured with astrocyte isolated from post neonatal (Day 1) rat brain. Moreover, neuronal differentiation was further promoted when the neuronal stem cells were cultured with astrocyte culture medium treated by EPO (10U/ml) showing increase of morphological differentiation, and expression of neuronal differentiation marker proteins, neurofilament, and tyrosine hydroxylase. The promoting effect of EPO-treated astrocyte medium was also found in the differentiation of PC12 cells. EPO-promoted morphological differentiation of neuronal stem cells as well as astrocytes was dose dependently reduced by treatment with anti-EPO receptor antibodies in culture with astrocyte culture medium. To clarify whether EPO itself or via production of well-known neurotropic factor could promote neuronal cell differentiation, we determined the level of neurotropic factors in the EPO-treated astrocytes. Compared to untreated astrocytes, EPO-treated astrocytes increased about 2-fold in beta-NGF and 3-4-fold in BMP2, but did not increase BNDF and NT-3 levels. Since the previous study showed that extracellular signal-regulated kinase (ERK) is involved in activation of astrocytes by EPO, we determined whether generation of neurotrophic factor may also be involved with the ERK pathway. In the presence of ERK inhibitor, PD98059, the generation of beta-NGF was diminished in a dose dependent manner consistent with the inhibiting effect on neuronal differentiation. These data demonstrate that EPO promotes neuronal cell differentiation through increased release of beta-NGF and BMP2 from astrocytes, and this effect may be associated with ERK pathway signals. 相似文献
920.