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Naif A. M. Almontashiri Ragnar O. Vilmundarson Nima Ghasemzadeh Sonny Dandona Robert Roberts Arshed A. Quyyumi Hsiao-Huei Chen Alexandre F. R. Stewart 《PloS one》2014,9(9)
Objective
Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a circulating protein that promotes degradation of the low density lipoprotein (LDL) receptor. Mutations that block PCSK9 secretion reduce LDL-cholesterol and the incidence of myocardial infarction (MI). However, it remains unclear whether elevated plasma PCSK9 associates with coronary atherosclerosis (CAD) or more directly with rupture of the plaque causing MI.Methods and Results
Plasma PCSK9 was measured by ELISA in 645 angiographically defined controls (<30% coronary stenosis) and 3,273 cases of CAD (>50% stenosis in a major coronary artery) from the Ottawa Heart Genomics Study. Because lipid lowering medications elevated plasma PCSK9, confounding association with disease, only individuals not taking a lipid lowering medication were considered (279 controls and 492 with CAD). Replication was sought in 357 controls and 465 with CAD from the Emory Cardiology Biobank study. PCSK9 levels were not associated with CAD in Ottawa, but were elevated with CAD in Emory. Plasma PCSK9 levels were elevated in 45 cases with acute MI (363.5±140.0 ng/ml) compared to 398 CAD cases without MI (302.0±91.3 ng/ml, p = 0.004) in Ottawa. This finding was replicated in the Emory study in 74 cases of acute MI (445.0±171.7 ng/ml) compared to 273 CAD cases without MI (369.9±139.1 ng/ml, p = 3.7×10−4). Since PCSK9 levels were similar in CAD patients with or without a prior (non-acute) MI, our finding suggests that plasma PCSK9 is elevated either immediately prior to or at the time of MI.Conclusion
Plasma PCSK9 levels are increased with acute MI. 相似文献234.
Sharifi Masoomeh Nazarinia Donya Ramezani Fatemeh Azizi Yaser Naderi Nasim Aboutaleb Nahid 《Molecular biology reports》2021,48(3):2507-2518
Molecular Biology Reports - Nesfatin-1 as a new energy-regulating peptide has been known to display a pivotal role in modulation of cardiovascular functions and protection against... 相似文献
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Parastoo Pourali Majid Baserisalehi Sima Afsharnezhad Javad Behravan Rashin Ganjali Nima Bahador Sepideh Arabzadeh 《Biometals》2013,26(1):189-196
The purpose of this study was the evaluation of two different temperatures on antibacterial activity of the biosynthesized silver nanoparticles. 38 silver nanoparticles-producing bacteria were isolated from soil and identified. Biosynthesis of silver nanoparticles by these bacteria was verified through visible light spectrophotometry. Two strains were relatively active for production of silver nanoparticles. These strains were subjected for molecular identification and recognized as Bacillus sp. and Acinetobacter schindleri. In the present study, the effect of temperatures was evaluated on structure and antimicrobial properties of the silver nanoparrticles by transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis and antimicrobial Agar well diffusion methods. The silver nanoparticles showed antibacterial activity against all the pathogenic bacteria; however, this property was lost after treatment of the silver nanoparticles by high temperatures (100 and 300 °C). TEM images showed that the average sizes of heated silver nanoparticles were >100 nm. However, these were <100 nm for non-heated silver nanoparticles. Although, XRD patterns showed the crystalline structure of heated silver nanoparticles, their antibacterial activities were less. This was possible because of the sizes and accordingly less penetration of the particles into the bacterial cells. In addition, elimination of the capping agents by heat might be considered another reason. 相似文献
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Iman Ahrari Armin Attar Nima Pourhabibi Zarandi Maryam Zakerinia Mohsen Khosravi Maharlooei Ahmad Monabati 《Molecular Biology》2013,47(5):685-691
Reports on the isolation of mesenchymal stromal cells (MSCs) from granulocyte colony stimulating factor mobilized peripheral blood (G-CSF-mobilized PB) using regular culturing techniques are controversial. Enrichment techniques such as CD133 isolation have increased the success rates. CD271 is a wellknown marker for enrichment of MSCs from bone marrow (BM). In the present study, we aimed to find out whether CD271 enrichment can help isolation of MSCs from G-CSF-mobiiized PB. Five G-CSF-mobilized PB samples were collected from the remnant parts of the bags used for BM transplantation. Five BM samples were used as the control. Mononuclear cells (MNCs) from both resources were collected and underwent magnetic sorting for CD271-positive cells. The isolated cells were cultured, undergoing flowcytometry and differentiation assays to determine if they fulfill MSCs characteristics. CD271-positive portion of G-CSF-mobilized PB did not yield any cell outgrowth but the BM counterpart could successfully form MSC colonies. Although the percentage of CD271+ cells showed no difference between BM-MNCs and G-CSF-mobilized PB-MNCs, hematopoietic markers such as CD45, CD34 and CD133 composed a higher percentage of CD271-positive cells in the G-CSF-tnobiiized PB group. Results obtained indicated that CD271 enrichment does not help isolation of MSCs from G-CSF-mobilized PB. In this source, almost all of the CD271+ cells are from hematopoietic origin and the frequency of MSCs is so low that possibly during the process of cell isolation most of them are lost and the isolation fails. 相似文献
239.
Maryam Khoshsokhan Mozaffar Shahrokh Kazempour Osaloo Roghayeh Oskoueiyan Kosar Naderi Saffar Atefe Amirahmadi 《Plant Systematics and Evolution》2013,299(1):197-208
A selection of Boraginaceae genera was used to obtain a framework for the phylogenetic position of some tribes belong to subfamily Boraginoideae and genera within tribe Eritrichieae (Heterocaryum, Rochelia, Eritrichium, Lappula, Lepechiniella, and Asperugo) and related species. Our results were produced on the basis of nrDNA ITS and cpDNAtrnL-F sequences. The combined nrDNA ITS trnL-F data confirm four main clades of Boraginoideae comprising Echiochileae, Boragineae, Lithospermeae, and Cynoglosseae s. l. (including Eritrichieae, Cynoglosseae s. str., and Myosotideae). The tribe Eritrichieae itself at the current status is paraphyletic; some members, for example Asperugo procumbens, Lepechiniella inconspicua, Myosotidium hortensia, and Cryptantha flavoculata are placed out of the core tribe Eritrichieae. The genus Heterocaryum is monophyletic and allied with a subclade of genera Lappula, Lepechiniella, Eritrichium, and Rochelia. Rochelia is monophyletic, but Eritrichium and Lappula are non-monophyletic. Lepechiniella is nested among a group of Lappula species. 相似文献
240.
Nima Hosseini Jazani Mojtaba Karimzad Ebrahim Mazloomi Mohammad Sohrabpour Zuhair Muhammad Hassan Hojjat Ghasemnejad Shiva Roshan-Milani Shahram Shahabi 《Microbes and infection / Institut Pasteur》2010,12(5):382-388
We have previously demonstrated the adjuvant activity of naloxone (NLX), a general opioid antagonist, using a DNA vaccine for herpes simplex virus type 1. Here, the adjuvant activity of NLX has been evaluated using a heat-killed Listeria monocytogenes (HKLM) vaccine as a model for general immunization against intracellular bacteria. BALB/c mice were divided into three groups: the Vac group received the HKLM vaccine alone; the NLX–Vac group received the HKLM vaccine in combination with the adjuvant NLX; and the control group received phosphate buffered saline (PBS). Our results indicate that the administration of NLX as an adjuvant enhances the ability of the HKLM vaccine to increase lymphocyte proliferation, delayed type hypersensitivity, and skewing of the immune response toward a T-helper 1 (Th1) pattern. Additionally, combination of NLX with the HKLM vaccine improves protective immunity against L. monocytogenes. In conclusion, administration of NLX as an adjuvant for the HKLM vaccine can enhance cell-mediated immunity and shift the immune response to Th1. 相似文献