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The Effect of Pulsed Magnetic Field on the Molecular Uptake and Medium Conductivity of Leukemia Cell
Zeinab Shankayi S. M. P. Firoozabadi Mahsa G. Mansurian 《Cell biochemistry and biophysics》2013,65(2):211-216
The cell membrane acts as a barrier that hinders free entrance of most hydrophilic molecules into the cell. Owing to the numerous applications, the introduction of non-permeate molecules into biologic cells has drawn considerable attention in the past years. The aim of our study was to investigate the effect of time-varying magnetic field on transmembrane molecular transport by measuring bleomycin cytotoxicity and conductivity modifying in K562 cells. The cells were exposed to magnetic pulses of 2.2 T strength peak and about 250-μs duration via Magstim stimulator and double 70-mm coil. Three different frequencies of 0.25, 1, and 10 Hz pulses for 56,112, and 28 numbers of pulses, respectively, were applied (nine experimental groups) and uptake and conductivity was measured in each group. Our results show that time-varying magnetic field increase transmembrane molecular transport and media conductivity; this enhancement is greater for 28 pulses with 1 Hz frequency. The observed uptake enhancement due to magnetic exposure is considerable. 相似文献
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Maryam Amiri Mohsen Basiri Hossein Eskandary Zeinab Akbarnejad Marzie Esmaeeli Yaser Masoumi-Ardakani 《Electromagnetic biology and medicine》2018,37(3):138-145
Glioblastoma multiforme (GBM) is a malignant brain cancer that causes high mortality in patients. GBM responds weakly to the common cancer treatments such as chemotherapy and radiotherapy and even surgery. Carboplatin is an alkylating agent widely used to treat cancer. However, resistance to this drug is a common problem in its use in cancer treatment. Concomitant exposure to extremely low-frequency electromagnetic fields (ELF-EMFs) and carboplatin is one unexplored possibility for overcoming this resistance. Indeed, many lines of evidence show that EMF affects cancer cells and drug action. In this study, we evaluated the effect of concomitant administration of carboplatin and EMF (50 Hz, 70 G) and also concomitant administration of carboplatin and static magnetic field (SMF) (70 G) on human glioma cell line (U-87). The results showed that cotreatment reduced the efficiency of carboplatin in U-87 cells, by decreasing caspase-3 in comparison to drug groups. Overall, EMF reduced the apoptotic effect of carboplatin, possibly through a redox regulation mechanism. Therefore, we have to avoid coadministration of magnetic field (MF) and carboplatin in tumor area, because the MF decreased the toxicity of the drug. However, further studies are needed to reveal the action mechanism of this combination therapeutic method. 相似文献
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Zeinab Ebrahimzadeh Angana Mukherjee Dave Richard 《International journal for parasitology》2018,48(1):13-25
Despite representing a small percentage of the cellular lipids of eukaryotic cells, phosphoinositides (PIPs) are critical in various processes such as intracellular trafficking and signal transduction. Central to their various functions is the differential distribution of PIP species to specific membrane compartments through the actions of kinases, phosphatases and lipases. Despite their importance in the malaria parasite lifecycle, the subcellular distribution of most PIP species in this organism is still unknown. We here localise several species of PIPs throughout the erythrocytic cycle of Plasmodium falciparum. We show that PI3P is mostly found at the apicoplast and the membrane of the food vacuole, that PI4P associates with the Golgi apparatus and the plasma membrane and that PI(4,5)P2, in addition to being detected at the plasma membrane, labels some cavity-like spherical structures. Finally, we show that the elusive PI5P localises to the plasma membrane, the nucleus and potentially to the transitional endoplasmic reticulum (ER). Our map of the subcellular distribution of PIP species in P. falciparum will be a useful tool to shed light on the dynamics of these lipids in this deadly parasite. 相似文献
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Objectives
Single nucleotide polymorphisms (SNPs), genetic background, and epigenetics play important roles in rheumatoid arthritis (RA). These factors can be useful in RA diagnosis, prognosis, and treatment response evaluation, particularly with the growing trends in personalized medicine. Therefore, categorizing classic genes and SNPs in RA can present an appropriate guideline for RA management.Discussion
Prognostic and diagnostic biomarkers play important roles in RA diagnosis and treatment. Categorizing SNPs is not an easy process yet, but selecting classic SNPs can be useful worldwide, according to basic similarities that exist in genomes. In this review, we compiled some of these RA-associated SNPs and biomarkers in a table, according to newly identified factors. The role of epigenetics in RA is undeniable; using epigenetic biomarkers like histone deacetylase (HDACs) can be useful in RA diagnosis and treatment. miRs such as miR-146a, miR-155, and miR-222 are useful in diagnosis and can be used in treatment by interfering with other factors’ functions. Interleukins (ILs) seem to be good prognostic and diagnostic markers and can be targeted in RA treatment.Conclusion
Using multiple types of biomarkers, such as genes, SNPs, and epigenetic biomarkers like HDACs can be useful in RA management and treatment. PTPN22, HLA-DR polymorphisms, miRs, and HDACs are considerable in RA susceptibility; hence, they can be valuable biomarkers in future studies. This article gathered separate information from approximately 100 articles to present useful biomarkers and polymorphisms in one review.39.
Objectives and Backgrounds
Cardiovascular events occure as a result of various risk factors, such as uric acid (UA), inflammation, hormones and other materials that induce C- reactive protein (CRP) expression. These factors lead to complement activation, and endothelial damages. Damaged endothelial cells release heparan sulfate which inhibits tissue factor activity and von Willed brand factor (VWVF) and causes aggregation. Finally this cascade of events cause platelets aggregation and leads to heart ischemia and cardiovascular events.Discussion
Anti-platelet therapy is an interesting premise. Anti-platelet resistance patients and bleeding as a result of using ticagrelor and prasugrel should be considered in this treatment methods. Anti-platelet drugs such as clopidogrel are prescribed in cardiovascular events. Platelets have VWF receptors and P2Y12 receptors on their surface, and thus, targeting these receptors can be useful in treatment. The active metabolites of clopidogrel bind to P2Y12R and inhibit ADP binding; thus, clopidogrel inhibits aggregation by interfering in several events as a result of the inhibition of ADP attachment to P2Y12R of the platelet. However, the polymorphisms of P2Y12 and other genes mentioned in Table 1 showed treatment resistance in anti-platelet therapy, highlighting that these SNPs can be helpful in anti-platelet therapy.Conclusion
The knowledge of these SNPs may decrease the number of unwanted effects that endanger patients with cardiovascular diseases and avoids ineffective anti-platelet therapy in several patients. Clopidogrel, ticagrelor, prasugrel, and aspirin and CYP2C19 and their SNPs are very important subjects in anti-platelet therapy. To present the importance of using pharmacogenetics in anti-platelet therapy, we discuss here the association between these drugs and the SNPs for therapeutic resistance.40.
Essential Oil and Bioactive Compounds Variation in Myrtle (Myrtus communis L.) as Affected by Seasonal Variation and Salt Stress
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Zeinab Vafadar Shoshtari Mehdi Rahimmalek Mohammad Reza Sabzalian Hossein Hosseini 《化学与生物多样性》2017,14(4)
The effect of different NaCl concentrations (control, 2, 4 and 6 dS/m) and three harvesting times in different seasons including spring (9 April), summer (5 July), and fall (23 September) was evaluated on essential oil (EO) yield, composition, phenolic, flavonoid content, and antioxidant activity of myrtle. Essential oil yield ranged from 0.2% in control and fall to 1.6% in moderate salinity (4 dS/m) and spring season. The main constituents obtained from gas chromatography/mass spectrometry analysis were α‐pinene, 1,8‐cineole, limonene, linalool, α‐terpineol, and linalyl acetate in which α‐pinene ranged from 11.70% in moderate and fall to 30.99% in low salinity (2 dS/m) and spring, while 1,8‐cineole varied from 7.42% in high salinity (6 dS/m) and summer to 15.45% in low salinity and spring, respectively. Salt stress also resulted in an increase in total phenolic, flavonoid content, and antioxidant activity. The highest antioxidant activity based on DPPH radical scavenging activity, reducing power (FTC) and β‐carotene/linoleic acid model systems was found in plants harvested in spring and summer in high stress condition. The lowest IC50 values obtained in 6 dS/m in spring (375.23 μg/ml) followed by summer (249.41 μg/ml) and fall (618.38 μg/ml). Eight major phenolic and flavonoid compounds were determined in three harvesting times using high performance liquid chromatography analysis. In overall, late harvesting time of myrtle in fall can lead to reduce the most of major EO components, while it can improve the amount of phenolic acids. 相似文献