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Imteyaz Ahmad Khan Sucharita Pilli Surendranath A Ritika Rampal Sudhir Kumar Chauhan Veena Tiwari Venigalla Pratap Mouli Saurabh Kedia Baibaswata Nayak Prasenjit Das Govind K. Makharia Vineet Ahuja 《PloS one》2016,11(3)
Background
Association of Mycobacterium avium subspecies paratuberculosis (MAP) and Crohn’s disease (CD) has been controversial due to contradictory reports. Therefore, we determined the prevalence of MAP in patients with CD and intestinal tuberculosis (ITB) and its association with clinical course.Methodology
Blood and intestinal biopsies were taken from 69 CD, 32 ITB patients and 41 patients with haemorrhoidal bleed who served as controls. qPCR targeting of MAP-specific IS900 gene was used to detect the presence of MAP DNA. qPCR results were further validated by sequencing. Immunohistochemistry (IHC) was used to detect the presence of MAP antigen in biopsy specimens. CD and ITB patients were followed-up for disease course and response to therapy.Principal Findings
The frequency of MAP-specific DNA in biopsies by qPCR was significantly higher in CD patients (23.2%, p = 0.03) as compared to controls (7.3%). No significant difference in intestinal MAP presence was observed between ITB patients (12.5%, p = 0.6) and controls (7.3%). MAP presence in blood of CD patients was 10.1% as compared to 4.9% in controls while no patients with ITB were found to be positive (p = 0.1). Using IHC for detection of MAP antigen, the prevalence of MAP in CD was 2.9%, 12.5% in ITB patients and 2.4% in controls. However, long-term follow-up of the patients revealed no significant associations between clinical characteristics and treatment outcomes with MAP positivity.Conclusion
We report significantly high prevalence of MAP in intestinal biopsies of CD patients. However, the presence of MAP does not affect the disease course and treatment outcomes in either CD or ITB patients. 相似文献44.
Mithun Das Jin Sha Bertha Hidalgo Stella Aslibekyan Anh N. Do Degui Zhi Dianjianyi Sun Tao Zhang Shengxu Li Wei Chen Sathanur R. Srinivasan Hemant K. Tiwari Devin Absher Jose M. Ordovas Gerald S. Berenson Donna K. Arnett Marguerite R. Irvin 《PloS one》2016,11(1)
In this study, we conducted an epigenome-wide association study of metabolic syndrome (MetS) among 846 participants of European descent in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN). DNA was isolated from CD4+ T cells and methylation at ~470,000 cytosine-phosphate-guanine dinucleotide (CpG) pairs was assayed using the Illumina Infinium HumanMethylation450 BeadChip. We modeled the percentage methylation at individual CpGs as a function of MetS using linear mixed models. A Bonferroni-corrected P-value of 1.1 x 10−7 was considered significant. Methylation at two CpG sites in CPT1A on chromosome 11 was significantly associated with MetS (P for cg00574958 = 2.6x10-14 and P for cg17058475 = 1.2x10-9). Significant associations were replicated in both European and African ancestry participants of the Bogalusa Heart Study. Our findings suggest that methylation in CPT1A is a promising epigenetic marker for MetS risk which could become useful as a treatment target in the future. 相似文献
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Achene morphology of Saussurea species (Asteraceae,Cardueae) in Korea and its systematic implications
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Balkrishna Ghimire Mi Jin Jeong Kyung Mee Lee Kweon Heo Cheul Ho Lee Gang Uk Suh 《Botanical journal of the Linnean Society. Linnean Society of London》2016,181(4):692-710
Achene size and shape, surface sculpturing, and pericarp and testa wall structure of 23 Korean Saussurea spp. were investigated using scanning electron microscopy (SEM) and light microscopy to evaluate the infrageneric relationships and assess their systematic significance. Achene size categories and thickness of the testa epidermis were distinguished using biometric measurements. Four basic types of surface pattern were observed: (1) lineate; (2) striate; (3) reticulate; and (4) colliculate. Saussurea rorinsanensis was found to have some unique achene characteristics, such as a fusiform achene, uniform pappus, presence of epidermal hairs and tangentially elongated, narrow testa epidermal cells. The characteristic achene features for species were found to be achene size and shape, hilum position, surface sculpture, pappus composition, morphology of the pericarp wall and thickness of the testa epidermis. Based on 16 morphological and achene characters, a cladistic analysis resolved three well‐supported clades, with S. eriophylla as the first‐branching taxon. Saussurea pulchella and S. japonica, both belonging to Saussurea subgenus Theodorea, were distant from each other in the 50% majority rule consensus tree and the character distribution cladogram. This cladistic analysis of achene morphology and anatomy should be regarded as giving us a tentative picture of the phylogenetics of Saussurea, and this study may serve as a reference for future hypotheses and studies on the characterization and classification of Saussurea spp. in Korea. 相似文献
46.
Nanocrystalline SrS phosphors doped with Ce3+ ions at different concentrations (0.5, 1, 1.5 and 2 mol%) are synthesized via the solid‐state diffusion method (SSDM), which is suitable for the large‐scale production of phosphors in industrial applications. The as‐prepared samples are characterized using an X‐ray diffraction (XRD) technique, field emission scanning electron microscopy (FESEM), high‐resolution transmission electron microscopy (HRTEM) and energy‐dispersive X‐ray (EDX) analysis. The optical properties of these phosphors are analyzed using reflectance spectra, photoluminescence spectra and afterglow decay curves. The cubic structure of the SrS phosphor is confirmed by XRD analysis and the crystallite size calculated by Scherer's formula using XRD data shows the nanocrystalline nature of the phosphors. No phase change is observed with increasing concentrations of Ce3+ ions. The surface morphology of the prepared phosphors is determined by FESEM, which shows a sphere‐like structure and good connectivity of the grains. The authenticity of the formation of nanocrystalline phosphors is examined by HRTEM analysis. Elemental compositional information for the prepared phosphors is gathered by EDX analysis. Photoluminescence studies reveal that the emission spectra of the prepared phosphor shows broad band emission centered at 458 and 550 nm due to the transition of electrons from the 5d → 4f energy levels. The afterglow decay characteristics of different as‐synthesized SrS:Ce3+ nanophosphors are conceptually described. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Pandey Manitosh Tiwari Satish Johri Sonia Biswal Bichitra K Sharma Chandresh Pandey Amit Kumar 《The protein journal》2022,41(3):424-433
The Protein Journal - Mycobacterium tuberculosis, the causative agent of tuberculosis, demonstrates immense plasticity with which it adapts to a highly dynamic and hostile host environment. This is... 相似文献
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An antisense RNA regulates the bidirectional silencing property of the Kcnq1 imprinting control region
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Thakur N Tiwari VK Thomassin H Pandey RR Kanduri M Göndör A Grange T Ohlsson R Kanduri C 《Molecular and cellular biology》2004,24(18):7855-7862
The Kcnq1 imprinting control region (ICR) located in intron 10 of the Kcnq1 gene is unmethylated on the paternal chromosome and methylated on the maternal chromosome and has been implicated in the manifestation of parent-of-origin-specific expression of six neighboring genes. The unmethylated Kcnq1 ICR harbors bidirectional silencer activity and drives expression of an antisense RNA, Kcnq1ot1, which overlaps the Kcnq1 coding region. To elucidate whether the Kcnq1ot1 RNA plays a role in the bidirectional silencing activity of the Kcnq1 ICR, we have characterized factor binding sites by genomic footprinting and tested the functional consequence of various deletions of these binding sites in an episome-based system. Deletion of the elements necessary for Kcnq1ot1 promoter function resulted in the loss of silencing activity. Furthermore, interruption of Kcnq1ot1 RNA production by the insertion of a polyadenylation sequence downstream of the promoter also caused a loss of both silencing activity and methylation spreading. Thus, the antisense RNA plays a key role in the silencing function of the ICR. Double-stranded RNA (dsRNA)-mediated RNA interference is unlikely to be involved, as the ICR is active irrespective of the simultaneous production of dsRNA from the genes it silences. 相似文献