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951.
BACKGROUND: Typical cytologic features of pulmonary hamartoma (PH) are usually smears of hyaline cartilage, fibrous tissue, smooth muscle, adipocytic components and respiratory epithelium. Cytologic features of adenomyomatous hamartoma, a special variant of PH, are not documented in the literature and are confused with epithelial neoplasm in the case of sparse stromal cellularity. CASE: A 59-year-old man presented with a solitary pulmonary nodule by chest radiograph at his routine health examination. Fine needle aspiration biopsy (FNAB) revealed numerous mucinous epithelial cells presenting predominantly in cohesive cellular sheets that suggested benign mucinous epithelial lesion. The patient underwent surgery for the tumor, and it was histologically proven to be an adenomyomatous hamartoma. CONCLUSION: An unusual type of PH could lead to misdiagnosis by FNAB in the case of few stromal components. This case demonstrates the wide spectrum of PH in FNAB and led us to consider PH as a differential diagnosis despite lack of chondromyxoid stromal components. 相似文献
952.
Phylogenetic Characterization of Two Novel Commensal Bacteria Involved with Innate Immune Homeostasis in Drosophila melanogaster
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Seong Woon Roh Young-Do Nam Ho-Won Chang Kyoung-Ho Kim Min-Soo Kim Ji-Hwan Ryu Sung-Hee Kim Won-Jae Lee Jin-Woo Bae 《Applied microbiology》2008,74(20):6171-6177
During a previous study on the molecular interaction between commensal bacteria and host gut immunity, two novel bacterial strains, A911T and G707T, were isolated from the gut of Drosophila melanogaster. In this study, these strains were characterized in a polyphasic taxonomic study using phenotypic, genetic, and chemotaxonomic analyses. We show that the strains represent novel species in the family Acetobacteraceae. Strain G707T, a highly pathogenic organism, represents a new species in the genus Gluconobacter, “Gluconobacter morbifer” sp. nov. (type strain G707 = KCTC 22116T = JCM 15512T). Strain A911T, dominantly present in the normal Drosphila gut community, represents a novel genus and species, designated “Commensalibacter intestini” gen. nov., sp. nov. (type strain A911 = KCTC 22117T = JCM 15511T). 相似文献
953.
Bae JS Cheong HS Kim JO Lee SO Kim EM Lee HW Kim S Kim JW Cui T Inoue I Shin HD 《Biochemical and biophysical research communications》2008,373(4):593-596
Copy number variation (CNV) is emerging as a new tool for understanding human genomic variation, but its relationship with human disease is not yet fully understood. The data for a total of 317,503 genotypes were collected for a genome-wide association study of subarachnoid aneurismal hemorrhage (SAH) in a Japanese population (cases and controls, n = 497) using Illumina HumanHap300 BeadChip®. To identify multi-allelic CNV markers, we visually inspected all genotype clusters of 317,503 SNP markers covering the whole genome using Illumina’s BeadStudio 3.0® software. As a result, we identified 597 multi-allelic CNV markers for common (copy loss frequency > 0.05) CNV regions in a Japanese population (n = 497). The identified CNV markers shared the following characteristics: enrichment of Hardy–Weinberg disequilibria, Mendelian inconsistency among families, and high missing genotype rate. All annotated information for those markers is summarized in our database (http://www.snp-genetics.com/user/srch.htm). In addition, we performed case-control association analyses of identified multi-allelic CNV markers with the risk of subarachnoid aneurysmal hemorrhage. One SNP marker (rs1242541) within a CNV region neighboring the Sel-1 suppressor of lin-12-like protein (SEL1L) was significantly associated with a risk of SAH (P = 0.0006). We also validated the CNV around rs1242541 using real-time quantitative polymerase chain reaction (PCR). Information and methods used in this study would be helpful for accurate genotyping of SNPs on CNV regions, which could be used for association analysis of SNP markers within CNV regions. 相似文献
954.
955.
Identification of a novel 4-hydroxyphenylpyruvate dioxygenase from the soil metagenome 总被引:1,自引:0,他引:1
Lee CM Yeo YS Lee JH Kim SJ Kim JB Han NS Koo BS Yoon SH 《Biochemical and biophysical research communications》2008,370(2):322-326
4-Hydroxyphenylpyruvate dioxygenase (HPPD) is a Fe(II)-dependent, non-heme oxygenase that converts 4-hydroxyphenylpyruvate to homogentisate. Essential cofactors, such as plastoquinone and tocopherol, are produced by HPPD-dependent anabolic pathways in plants. To isolate a novel hppd using culture-independent method, a cosmid metagenomic library was constructed from soil in Korea. Screening of Escherichia coli metagenomic libraries led to the identification of a positive clone, YS103B, producing dark brown pigment in Luria-Bertani medium supplemented with l-tyrosine. In vitro transposon mutagenesis of YS103B showed that the 1.3 kb insert was sufficient to produce the hemolytic brown pigment. Sequence analysis of YS103B disclosed one open reading frame encoding a 41.4 kDa protein with the well-conserved prokaryotic oxygenase motif of the HPPD family of enzymes. The HPPD-specific β-triketone herbicide, sulcotrione, inhibited YS103B pigmentation. The recombinant protein expressed in E. coli generated homogentisic acid. Thus, we present the successful heterologous expression of a previously uncharacterized hppd gene from an uncultured soil bacterium. 相似文献
956.
Lim SY Chung WY Lee HK Park MS Park HG 《Biochemical and biophysical research communications》2008,376(4):633-636
The fluorogenic 1,3-Huisgen dipolar cycloaddition reaction was used as part of a novel immobilization strategy of PNA capture probes on a microarray. By using this click chemistry, azidocoumarin-anchored PNA probes were immobilized on phenyl acetylene-modified glass slides with the simultaneous generation of the fluorescent triazolylcoumarin moiety. Since the emitting moieties are generated in the immobilization reaction itself, fluorescent signals can be used to directly monitor the integrity of immobilization in a nondestructive manner. By using this strategy, PNA microarrays were prepared and successfully employed to perform microarray-based diagnosis of selected mutations in the breast cancer susceptibility gene BRCA1. 相似文献
957.
Yeo KJ Kwak SN Kim HJ Cheong C Kim MH Jeon YH 《Biochemical and biophysical research communications》2008,376(2):409-413
Bacterial histidine kinases play an important role in the response to external stimuli. Structural studies of the histidine kinase transmembrane domain are challenging due to difficulties in protein expression and sample preparation. After carrying out expression screening of a series of histidine kinases, we investigated sample preparation methods for obtaining high quality samples of the periplasmic and transmembrane domain (PTD) of the bacterial histidine kinase SCO3062. Various sample conditions were tested for their ability to give homogeneous NMR spectra of the SCO3062 PTD with well-resolved resonances. Circular dichroism and 3D 15N-edited NOESY spectrum results demonstrate that the SCO3062 PTD is predominantly α-helical. This method should be applicable to the NMR analysis of other transmembrane proteins. 相似文献
958.
Park JH Bang SW Jeon Y Kang S Hwang DS 《Biochemical and biophysical research communications》2008,365(3):575-582
In model organisms, MCM10 is required for forming the pre-initiation complex for initiation of chromosome replication and is involved in the elongation step. To investigate the role of MCM10 in human chromosome replication, we used small interfering RNA (siRNA) in MCM10-knockdown experiments and found that knockdown accumulated S and G2 phase cells. The chromosome replication of MCM10-knockdown cells was slowed during early and mid S phases, although Cdc45, Polα, and PCNA proteins were loaded onto the chromatin, and was aberrant during late S phase. Our results indicate that MCM10 is essential for the efficient elongation step of chromosome replication. 相似文献
959.
Recently, histone H4 lysine 20 and H3 lysine 79 methylations were functionally linked to DNA damage checkpoint. The crosstalk between histone methylation and the S-M checkpoint, however, has remained unclear. Here, we show that H3 lysine 9 (K9) and lysine 36 (K36) methylations catalyzed by two histone methyltransferases Clr4 and Set2 are involved in hydroxyurea (HU)-induced replication checkpoint. The clr4-set2 double mutants besides histone H3-K9 and K36 double mutants exhibited HU-sensitivity, a defective HU-induced S-M checkpoint, and a significant reduction of HU-induced phosphorylation of Cdc2. Intriguingly, the clr4-set2 double mutations impaired the HU-induced accumulation of a mitotic inhibitor Mik1. Double mutants in Alp13 and Swi6, which can specifically bind to H3-K36 and K9 methylations, exhibited phenotypes similar to those of the clr4-set2 mutants. Together, these findings suggest that methylations of histone H3-K9 and K36 by Clr4 and Set2 are functionally linked to DNA replication checkpoint via accumulation of Mik1. 相似文献
960.
Cho SW Her SJ Sun HJ Choi OK Yang JY Kim SW Kim SY Shin CS 《Biochemical and biophysical research communications》2008,367(2):399-405
Secreted frizzled-related proteins (sFRPs) are modulators of Wnt signaling. This study was undertaken for definitive assessment of contribution of different sFRPs in osteoblastic differentiation of mesenchymal progenitor cells and apoptosis of osteoblasts. Treatment of C3H10T1/2 cells with sFRP-2 at concentrations of 10, 50, and 100 nM and sFRP-4 at low concentrations (5 nM) significantly increased Wnt-3A-induced alkaline phosphatase (ALP) activities, whereas sFRP-1 or 3 did not. Retroviral transduction of the sFRP-2 but not other sFRPs also significantly enhanced ALP activity induced by β-glycerophosphate and ascorbic acid. Furthermore, transfection of all the sFRP expression vectors significantly increased β-catenin/TCF reporter activity and the effects were most prominent with sFRP-2 and -4. In osteoblast apoptosis assay, only sFRP-3 increased etoposide-induced apoptosis in MC3T3-E1 mouse osteoblasts. In conclusion, we found that different repertoires of sFRPs exert differential effects on osteoblastic differentiation of mouse mesenchymal cells and cellular apoptosis of mouse osteoblasts in vitro. 相似文献