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41.
Azita Bahrami Alireza Farasat Leila Zolghadr Yalda Sabaghi Farnaz PourFarzad Nematollah Gheibi 《Cell biochemistry and function》2024,42(1):e3900
The deadliest type of skin cancer, malignant melanoma, is also the reason for the majority of skin cancer-related deaths. The objective of this article was to investigate the efficiency of free caffeic acid phenethyl ester (CAPE) and liposomal CAPE in inducing apoptosis in melanoma cells (A375) in in vitro. CAPE was loaded into liposomes made up of hydrogenated soybean phosphatidylcholine, cholesterol, and 1,2-distearoyl-sn-glycero-3 phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000], and their physicochemical properties were assessed. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test was performed for comparing the cytotoxicity of free CAPE and liposomal CAPE at dosages of 10, 15, 25, 50, 75 and the highest dose of 100 μg/mL for period of 24 and 48 h on A375 cell line to calculate IC50. Apoptosis and necrosis were evaluated in A375 melanoma cancer cells using flow cytometry. Atomic force microscopy was utilized to determine the nanomechanical attributes of the membrane structure of A375 cells. To determine whether there were any effects on apoptosis, the expression of PI3K/AKT1 and BAX/BCL2 genes was analyzed using the real-time polymerase chain reaction technique. According to our results, the maximum amount of drug release from nanoliposomes was determined to be 91% and the encapsulation efficiency of CAPE in liposomes was 85.24%. Also, the release of free CAPE was assessed to be 97%. Compared with liposomal CAPE, free CAPE showed a greater effect on reducing the cancer cell survival after 24 and 48 h. Therefore, IC50 values of A375 cells treated with free and liposomal CAPE were calculated as 47.34 and 63.39 μg/mL for 24 h. After 48 h of incubation of A375 cells with free and liposomal CAPE, IC50 values were determined as 30.55 and 44.83 μg/mL, respectively. The flow cytometry analysis revealed that the apoptosis induced in A375 cancer cells was greater when treated with free CAPE than when treated with liposomal CAPE. The highest nanomechanical changes in the amount of cell adhesion forces, and elastic modulus value were seen in free CAPE. Subsequently, the greatest decrease in PI3K/AKT1 gene expression ratio occurred in free CAPE. 相似文献
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Farshid Bahrami Mathieu Maisonneuve Michel Meunier Arthur O. Montazeri Yujin Kim Nazir P. Kherani J. Stewart Aitchison Mo Mojahedi 《Journal of biophotonics》2017,10(2):271-277
A plasmon waveguide resonance (PWR) sensor is proposed for studying the interaction between gold nanoparticles and proteins. The ability of the PWR sensor to operate in both TM and TE Polarizations, i.e. its polarization diversity, facilitates the simultaneous spectroscopy of the nanoparticles surface reactions using both polarizations. The response of each polarization to streptavidin‐biotin binding at the surface of gold nanoparticles is investigated in real time. Finally, using the principles of multimode spectroscopy, the nanoparticle's surface reactions are decoupled from the bulk solution refractive index variations.
45.
Jafar Zolala Ahmad-Reza Bahrami Mohammad Farsi Maryam M. Matin Vahid-Reza Yassaee 《Molecular breeding : new strategies in plant improvement》2009,24(1):17-24
The most familiar enzyme in mutation screening through heteroduplex analysis, CEL I, has been isolated from celery of the
Apiaceae family. In this study, in a search for new sources with the same or better enzymatic activity, we studied the mismatch-cleavage
activity of plant juice extracts from several Apiaceae plants (celery, carrot, coriander, parsley, dill, and fennel). This study was then followed by investigation of the level
of CEL I gene expression in these plants. Mismatch-cleavage activity of fennel and dill juice extracts was lower than that
of celery juice extract, and levels of CEL I mRNA expression in these plants were substantially higher than in celery. In
contrast, the ability of juice extract from a local cultivar of parsley to cleave heteroduplex DNA substrates was clearly
more than that of celery juice extract, whereas the level of CEL I gene expression in parsley was obviously lower than in
celery. We concluded that there are multiple mismatch-cleaving enzymes collaborating in digestion of heteroduplex DNA substrates
by plant juice extracts. 相似文献
46.
A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33?±?3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0?ppb (control), 800?ppb Cr-L-Met (T(1)), 1,200?ppb Cr-L-Met (T(2)) or 800?ppb CrCl(3) (T(3)), and 1,200?ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42?days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42?days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p?0.05). 相似文献
47.
Mehdi Imani Yaser Bahrami Hossein Zarei Jaliani Sussan Kaboudanian Ardestani 《The protein journal》2014,33(5):465-473
Calprotectin (CP) is widely considered to have diverse roles including growth inhibitory and apoptosis induction in a number of tumor cell lines and antimicrobial activities. As CP has been proposed to bind metal ions with high affinity, we have studied its functional and primarily its structural behavior upon Zn2+ and Mn2+ chelation solely and along with Ca2+. We employed fluorescence spectroscopy and circular dichroism to determine the resulting modifications. Based upon our findings it is clear that treating CP with ions effectively weakened its natural growth inhibitory activity. Moreover, structural analysis of Zn2+ and Mn2+-treated CPs indicated remarkable alterations in the regular secondary structures in favor of irregular structures while Zn2+ and Mn2+ treatment of CP after incubation with Ca2+ displayed no remarkable shifts. Tertiary structure investigation using fluorescence spectroscopy showed that CP undergoes conformational changes upon Zn2+ and Mn2+ treatment whereby Trp residues of protein is slightly exposed to the hydrophilic environment, compactness of CP is compromised, whereas in Ca2+-treated CP, the tertiary structure integrity is intact upon Zn2+ and Mn2+ chelation. Interestingly, CP structural modifications upon Zn2+ and Mn2+ treatment was significantly comparable, probably due to similar radii and charges of ions. Taken all together, we have concluded that CP maintains its normal nature in Ca2+-loaded state when treated with Zn2+ and Mn2+ ions. It can be suggested that Ca2+ not only stabilize CP structure but also helps CP to keep its structure upon metal ions chelation which is involved in host organism defense system. 相似文献
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Amir Reza Sadrolhosseini A. S. M. Noor Afarin Bahrami H. N. Lim Zainal Abidin Talib Mohd. Adzir Mahdi 《PloS one》2014,9(4)
Polypyrrole multi-walled carbon nanotube composite layers were used to modify the gold layer to measure heavy metal ions using the surface plasmon resonance technique. The new sensor was fabricated to detect trace amounts of mercury (Hg), lead (Pb), and iron (Fe) ions. In the present research, the sensitivity of a polypyrrole multi-walled carbon nanotube composite layer and a polypyrrole layer were compared. The application of polypyrrole multi-walled carbon nanotubes enhanced the sensitivity and accuracy of the sensor for detecting ions in an aqueous solution due to the binding of mercury, lead, and iron ions to the sensing layer. The Hg ion bonded to the sensing layer more strongly than did the Pb and Fe ions. The limitation of the sensor was calculated to be about 0.1 ppm, which produced an angle shift in the region of 0.3° to 0.6°. 相似文献
50.
Humans stand out from other animals in that they are able to explicitly report on the reliability of their internal operations. This ability, which is known as metacognition, is typically studied by asking people to report their confidence in the correctness of some decision. However, the computations underlying confidence reports remain unclear. In this paper, we present a fully Bayesian method for directly comparing models of confidence. Using a visual two-interval forced-choice task, we tested whether confidence reports reflect heuristic computations (e.g. the magnitude of sensory data) or Bayes optimal ones (i.e. how likely a decision is to be correct given the sensory data). In a standard design in which subjects were first asked to make a decision, and only then gave their confidence, subjects were mostly Bayes optimal. In contrast, in a less-commonly used design in which subjects indicated their confidence and decision simultaneously, they were roughly equally likely to use the Bayes optimal strategy or to use a heuristic but suboptimal strategy. Our results suggest that, while people’s confidence reports can reflect Bayes optimal computations, even a small unusual twist or additional element of complexity can prevent optimality. 相似文献