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891.
Ju Yeon Ban Su Kang Kim Sung Wook Kang Kyung Lim Yoon Joo-Ho Chung 《Life sciences》2010,86(19-20):756-759
AimsThis study was conducted to investigate the associations between single nucleotide polymorphisms (SNPs) of matrix metalloproteinases (MMPs) and Kawasaki disease (KD) in the Korean population.Main methodsA total 0f 101 KD patients and 306 healthy controls were examined. MMP7 (rs10502001, G/A, Arg77His), MMP11 (rs738792, T/C, Ala38Val), MMP12 (rs652438, A/G, Ile357Val) and MMP26 (rs2499953, A/G, Lys43Glu) genes were genotyped from the genomic DNA using direct sequencing. The results were then analyzed using logistic regression models, adjusting for gender as covariates.Key findingsThe four SNPs were in Hardy–Weinberg equilibrium. Only the MMP11 polymorphism (rs738792) was associated with KD. The SNP (rs738792) showed a statistically significant association with KD in the codominant (OR = 1.61, 95% CI = 1.11–2.34, P = 0.011) and dominant (OR = 1.92, 95% CI = 1.21–3.06, P = 0.006) models. However, there was no association between polymorphisms of other MMP genes and KD.SignificanceOverall, the results of this study indicate that MMP11 polymorphism may be associated with KD in the Korean population. 相似文献
892.
The use of 16S rRNA gene has been a “golden” method to determine the diversity of microbial communities in environmental samples, phylogenetic relationships of prokaryotes and taxonomic position of newly isolated organisms. However due to the presence of multiple heterogeneous 16S rRNA gene copies in many strains, the interpretation of microbial ecology via 16S rRNA sequences is complicated. Purpose of present paper is to demonstrate the extent to which the multiple heterogeneous 16S rRNA gene copies affect RFLP patterns and DGGE profiles by using the genome database. In present genome database, there are 782 bacterial strains in total whose genomes have been completely sequenced and annotated. Among the total strains, 639 strains (82%) possess multiple 16S rRNA gene copies, 415 strains (53%) whose multiple copies are heterogeneous in sequences as revealed by alignment, 236 strains (30%) whose multiple copies show different restrict patterns by CSP6I+HinfI, MspI+RsaI or HhaI as analyzed in silico. Polymorphisms of the multiple copies in certain strains were further characterized by G+C% and phy-logentic distances based on the sequences of V3 region, which are linked to DGGE patters. Polymorphisms of a few strains were shown as examples. Using artificial communities, it is demonstrated that the presence of multiple heterogeneous 16S rRNA gene copies potentially leads to over-estimation of the diversity of a community. It is suggested that care must be taken when interpreting 16S rRNA-based RFLP and DGGE data and profiling an environmental community. 相似文献
893.
The use of 16S rRNA gene has been a "golden" method to determine the diversity of microbial communities in environmental samples, phylogenetic relationships of prokaryotes and taxonomic position of newly isolated organisms. However due to the presence of multiple heterogeneous 16S rRNA gene copies in many strains, the interpretation of microbial ecology via 16S rRNA sequences is complicated. Purpose of present paper is to demonstrate the extent to which the multiple heterogeneous 16S rRNA gene copies affect RFLP patterns and DGG E profiles by using the genome database. In present genome database, there are 782 bacterial strains in total whose genomes have been completely sequenced and annotated. Among the total strains, 639 strains (82%) possess multiple 16S rRNA gene copies, 415 strains (53%) whose multiple copies are heterogeneous in sequences as revealed by alignment, 236 strains (30%) whose multiple copies show different restrict patterns by CSP61 + Hinfl, MspI + Rsal or HhaI as analyzed in silico. Polymorphisms of the multiple copies in certain strains were further characterized by G + C% and phylogentic distances based on the sequences of V3 region, which are linked to DGGE patters. Polymorphisms of a few strains were shown as examples. Using artificial communities, it is demonstrated that the presence of multiple heterogeneous 16S rRNA gene copies potentially leads to over-estimation of the diversity of a community. It is suggested that care must be taken when interpreting 16S rRNA-based RFLP and DGGE data and profiling an environmental community. 相似文献
894.
895.
Su Jung Park Kyung Jin Kwak Hyun Ju Jung Hwa Jung Lee Hunseung Kang 《Phytochemistry》2010,71(5-6):543-547
Among the four cold shock domain proteins (CSDPs) identified in Arabidopsis thaliana, it has recently been shown that CSDP1 harboring seven CCHC-type zinc fingers, but not CSDP2 harboring two CCHC-type zinc fingers, function as a RNA chaperone during cold adaptation. However, the structural features relevant to this differing RNA chaperone activity between CSDP1 and CSDP2 remain largely unknown. To determine which structural features are necessary for the RNA chaperone activity of the CSDPs, the importance of the N-terminal cold shock domain (CSD) and the C-terminal zinc finger glycine-rich domains of CSDP1 and CSDP2 were assessed. The results of sequence motif-swapping and deletion experiments showed that, although the CSD itself harbored RNA chaperone activity, the number and length of the zinc finger glycine-rich domains of CSDPs were crucial to the full activity of the RNA chaperones. The C-terminal domain itself of CSDP1, harboring seven CCHC-type zinc fingers, also has RNA chaperone activity. The RNA chaperone activity and nuclei acid-binding property of the native and chimeric proteins were closely correlated with each other. Collectively, these results indicate that a specific modular arrangement of the CSD and the zinc finger domain determines both the RNA chaperone activity and nucleic acid-binding property of CSDPs; this, in turn, contributes to enhanced cold tolerance in plants as well as in bacteria. 相似文献
896.
Background
Because of the increasing quantity and high toxicity to humans of polycyclic aromatic hydrocarbons (PAHs) in the environment, several bioremediation mechanisms and protocols have been investigated to restore PAH-contaminated sites. The transport of organic contaminants among plant cells via tissues and their partition in roots, stalks, and leaves resulting from transpiration and lipid content have been extensively investigated. However, information about PAH distributions in intracellular tissues is lacking, thus limiting the further development of a mechanism-based phytoremediation strategy to improve treatment efficiency.Results
Pyrene exhibited higher uptake and was more recalcitrant to metabolism in ryegrass roots than was phenanthrene. The kinetic processes of uptake from ryegrass culture medium revealed that these two PAHs were first adsorbed onto root cell walls, and they then penetrated cell membranes and were distributed in intracellular organelle fractions. At the beginning of uptake (< 50 h), adsorption to cell walls dominated the subcellular partitioning of the PAHs. After 96 h of uptake, the subcellular partition of PAHs approached a stable state in the plant water system, with the proportion of PAH distributed in subcellular fractions being controlled by the lipid contents of each component. Phenanthrene and pyrene primarily accumulated in plant root cell walls and organelles, with about 45% of PAHs in each of these two fractions, and the remainder was retained in the dissolved fraction of the cells. Because of its higher lipophilicity, pyrene displayed greater accumulation factors in subcellular walls and organelle fractions than did phenanthrene.Conclusions
Transpiration and the lipid content of root cell fractions are the main drivers of the subcellular partition of PAHs in roots. Initially, PAHs adsorb to plant cell walls, and they then gradually diffuse into subcellular fractions of tissues. The lipid content of intracellular components determines the accumulation of lipophilic compounds, and the diffusion rate is related to the concentration gradient established between cell walls and cell organelles. Our results offer insights into the transport mechanisms of PAHs in ryegrass roots and their diffusion in root cells. 相似文献897.
Kaimian Li Wenli Zhu Kang Zeng Zhenwen Zhang Jianqiu Ye Wenjun Ou Samrina Rehman Bruria Heuer Songbi Chen 《Proteome science》2010,8(1):10
Background
Proteomics is increasingly becoming an important tool for the study of many different aspects of plant functions, such as investigating the molecular processes underlying in plant physiology, development, differentiation and their interaction with the environments. To investigate the cassava (Manihot esculenta Crantz) proteome, we extracted proteins from somatic embryos, plantlets and tuberous roots of cultivar SC8 and separated them by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). 相似文献898.
So-Young Bang Tae-Un Han Chan-Bum Choi Yoon-Kyoung Sung Sang-Cheol Bae Changwon Kang 《Arthritis research & therapy》2010,12(3):R115
Introduction
Anti-cyclic citrullinated peptide autoantibodies (anti-CCP) are the most specific serologic marker for rheumatoid arthritis (RA). Genetic polymorphisms in a citrullinating (or deiminating) enzyme, peptidyl arginine deiminase type IV (PADI4) have been reproducibly associated with RA susceptibility in several populations. We investigated whether PADI4 polymorphisms contribute to anti-CCP-negative as well as -positive RA, whether they influence disease severity (erosive joint status), and whether they interact with two major risk factors for RA, Human Leukocyte Antigen-DRB1 (HLA-DRB1) shared epitope (SE) alleles and smoking, depending on anti-CCP and erosive joint status. 相似文献899.
草原沙漠化过程中植物叶面积的变化及其与土壤因子的关系 总被引:2,自引:0,他引:2
在自然状态下,对沙质草原沙漠化过程中主要植物叶面积变化及其与土壤因子的关系进行了研究。结果表明:随着沙漠化加剧,羊草和糙隐子草的比叶面积在沙漠化初期(梯度Ⅰ)下降显著(P0.01),菊叶萎陵菜和冰草的比叶面积在沙漠化后期(梯度Ⅲ)下降显著(P0.05),寸草苔比叶面积下降不显著(P0.05),冷蒿比叶面积从沙漠化中、后期开始显著增加(P0.05),扁蓿豆比叶面积从沙漠化初期开始显著增大(P0.01);羊草、糙隐子草和冷蒿的叶面积指数总体上呈显著下降趋势(P0.01),扁蓿豆叶面积指数显著增加(P0.01);羊草、糙隐子草叶面积指数与土壤粘粒、C、N含量、土壤含水量呈显著正相关(P0.01),与土壤C/N比呈显著负相关(P0.01);冷蒿和扁蓿豆叶面积指数与土壤因子的相关性和上述二者正好相反(P0.05);在叶面积指数与土壤因子线性拟合中,糙隐子草叶面积指数与土壤C/N拟合最高(R2=1),其次是羊草叶面积指数与土壤含水量的拟合(R2=0.992),扁蓿豆叶面积指数与土壤C/N拟合最低(R2=0.268)。土壤C/N是影响草原沙漠化过程中共有种叶面积的关键因子(P0.05),其影响大小为糙隐子草羊草冷蒿扁蓿豆。 相似文献
900.
Inja Lim Jihyun Yun Jung‐Ha Kim Young‐Ku Kang Nari Kim Jin Han Hyoweon Bang Jae‐Hong Ko 《Birth defects research. Part B, Developmental and reproductive toxicology》2010,89(3):201-206
BACKGROUND: This study was conducted to evaluate the occurrence and fate of fetal lumbar rib induced by Scutellariae radix (SR) in rats. METHODS: Water extracts of SR were orally administered to pregnant rats from day 7 to day 17 of gestation at a dose of 186 mg/kg/day, equivalent to 25 g/kg of starting material, representing a 100‐fold increase over typical human intake level. RESULTS: The incidence of fetal lumbar rib in the SR‐treated group was increased on gestational day 20 and then decreased on postnatal day 50. The weight of fetuses in the SR‐treated group tended to be less than that in the control group. Alkaline phosphatase in SR‐treated dams was increased on gestational day 20, but was decreased on postnatal day 50. There were no significant differences between the vehicle control and SR‐treated groups in maternal body weight, embryological, histopathological, hematological, and serum biochemical changes. CONCLUSIONS: The present data suggest that the appearance of lumbar rib induced by SR is a transient fetal variation rather than teratogenicity or maternal toxicity. Birth Defects Res (Part B) 89:201–206, 2010. © 2010 Wiley‐Liss, Inc. 相似文献