657 research outputs found
Mitochondrial apoptosis induced by Chamaemelum nobile extract in breast cancer cells
Chamaemelum nobile (Asteraceae) commonly known as ‹Roman chamomile› is a medicinal plant used for numerous diseases in traditional medicine, although its anticancer activity is unknown. The present study was carried out to investigate the anticancer as well as apoptotic activity of ethyl acetate fraction of C. nobile on different cancerous cell lines. The cells were treated with varying concentrations (0.001-0.25 mg/mL) of this fraction for 24, 48 and 72 h. Apoptosis induced in MCF-7 cells following treatment with ethyl acetate fraction was measured using Annexin V/PI, flowcytometry and western blotting analysis. The results showed that C. nobile ethyl acetate fraction revealed relatively high antiproliferative activity on MCF-7 cells; however, it caused minimal growth inhibitory response in normal cells. The involvement of apoptosis as a major cause of the fraction-induced cell death was confirmed by annexin-V/PI assay. In addition, ethyl acetate fraction triggered the mitochondrial apoptotic pathway by decreasing the Bcl-2 as well as increasing of Bax protein expressions and subsequently increasing Bax/Bcl-2 ratio. Furthermore, decreased proliferation of MCF-7 cells in the presence of the fraction was associated with G2/M phase cell cycle arrest. These findings confirm that ethyl acetate fraction of C.nobile may contain a diversity of phytochemicals which suppress the proliferation of MCF-7 cells by inducing apoptosis. © 2016 by School of Pharmacy Shaheed Beheshti University of Medical Sciences and Health Services
Prevalence of human respiratory syncytial virus circulating in Iran
Respiratory syncytial virus (RSV) is a leading cause of acute respiratory infection during early childhood and is associated with a great burden on patients, parents, and society. While no treatment is yet available, results from recent phase 2 clinical trials of cell-entry inhibitors and RSV vaccines are promising. To prepare for introduction of these novel therapeutics, good understanding of its molecular epidemiology and continuous RSV surveillance data are necessary. This paper provides an overview of RSV prevalence and genotype distribution in Iran from 1996 to 2013. This meta-analysis includes 21 published studies. In total, 775 (18.7) of 4140 respiratory specimens were positive for RSV infection. The male-female ratio of RSV-positive patients was 1.5:1. Significant peaks of RSV infection were detected during the cold season (November-March). RSV infection was mainly observed in patients <2 years of age. Phylogenetic studies showed that genotypes GA1, GA2, GA5, and BA co-circulated in Iran in 2007-2013. This review highlights the necessity of introducing standard molecular surveillance programs to inform the epidemiological, clinical, and pathological characteristics of various RSV genotypes. Improved understanding of the molecular epidemiology will be useful for development of novel RSV therapeutics. © 2015 King Saud Bin Abdulaziz University for Health Sciences
Modeling of karst and alluvial springs discharge in the central Alborz highlands and on the Caspian southern coasts
Springs are the important water resources, which thier study is necessary in terms of their management and exploitation. In northern Iran, the karst springs locate in the central Alborz highlands and alluvial springs on the Caspian southern coasts.The Karst and alluvial springs discharge is variable because of different conditions in terms of aquifer, topography and precipitation .This study has been done to simulate the karst and alluvial springs discharge and to compare their hydrologic conditions. So, 80 karst springs and 82 alluvial springs were investigated in central Alborz and on the Caspian southern coasts. Two models were presented to simulate the karst and alluvial springs discharge using Multivariate Regression analysis (SPSS software).Then, their efficiency was considered. Finally, the models and the results of regression analyses were compared. The results showed that the most important factors of the karst springs discharge are aquifer formation (its porosity) and site elevation, but about the alluvial springs, the hydraulic conductivity of aquifer formation and aquifer depth are the most important factors
Flood hazard zoning using geographic information system (GIS) and HEC-RAS model (Case study: Rasht City)
Rivers are important water resources for human life, but sometimes cause irreparable damages. The flood plains
are fertile terrains which are endangered by flood. Flood hazard mapping is one of the basic methods in flood
fighting. In order to decline flood damages, the simulation of the hydraulic behavior of the rivers during flood
occurrence is very important. In this study, areas that are flooded were zoned along Siahrood and Goharrood
rivers (Rasht City, northern Iran). The rivers bed and banks terrains of Goharrood and Siahrood were simulated
using HEC-GeoRAS extension and digital map (scale: 1000). Pick discharges with different return periods were
estimated using stochastic analysis. HEC-RAS software and geographical information system were applied for
simulating the hydraulic behavior of the rivers and providing flood zoning map. The GIS was an efficient tool for
data-processing and mapping stages. Finally, the flood zones associated with 2, 10, 25, 50, 100 and 200 years
return periods were mapped and necessary analysis were conducted during the present research. The results
showed that some parts of Rasht City (river bank terrains) are endangered flood hazard
Opioids and viral infections: A double-edged sword
Opioids and their receptors have received remarkable attention because they have the ability to alter immune function, which affects disease progression. In vitro and in vivo findings as well as observations in humans indicate that opioids and their receptors positively or negatively affect viral replication and virus-mediated pathology. The present study reviews recent insights in the role of opioids and their receptors in viral infections and discusses possible therapeutic opportunities. This review supports the emerging concept that opioids and their receptors have both favorable and unfavorable effects on viral disease, depending on the type of virus. Targeting of the opioid system is a potential option for developing effective therapies; however caution is required in relation to the beneficial functions of opioid systems. © 2016 Tahamtan, Tavakoli-Yaraki, Mokhtari-Azad, Teymoori-Rad, Bont, Shokri and Salimi
Evaluation of effective resistances in pseudo-distance-regular resistor networks
In Refs.[1] and [2], calculation of effective resistances on distance-regular
networks was investigated, where in the first paper, the calculation was based
on the stratification of the network and Stieltjes function associated with the
network, whereas in the latter one a recursive formula for effective
resistances was given based on the Christoffel-Darboux identity. In this paper,
evaluation of effective resistances on more general networks called
pseudo-distance-regular networks [21] or QD type networks \cite{obata} is
investigated, where we use the stratification of these networks and show that
the effective resistances between a given node such as and all of the
nodes belonging to the same stratum with respect to
(, belonging to the -th stratum with respect
to the ) are the same. Then, based on the spectral techniques, an
analytical formula for effective resistances such that
(those nodes , of
the network such that the network is symmetric with respect to them) is given
in terms of the first and second orthogonal polynomials associated with the
network, where is the pseudo-inverse of the Laplacian of the network.
From the fact that in distance-regular networks,
is satisfied for all nodes
of the network, the effective resistances
for ( is diameter of the network which
is the same as the number of strata) are calculated directly, by using the
given formula.Comment: 30 pages, 7 figure
The pro-apoptosis effects of Echinacea purpurea and Cannabis sativa extracts in human lung cancer cells through caspase-dependent pathway
Background: Considering the advantages of using medicinal herbs as supplementary treatments to sensitize conventional anti-cancer drugs, studying functional mechanisms and regulatory effects of Echinacea purpurea (as a non-cannabinoid plant) and Cannabis sativa (as a cannabinoid plant) are timely and required. The potential effects of such herbs on lung cancer cell growth, apoptosis, cell cycle distribution, cellular reactive oxygen species (ROS) level, caspase activity and their cannabinomimetic properties on the CB2 receptor are addressed in the current study. Methods: The cytotoxic effect of both herb extracts on the growth of lung cancer cells (A549) was assessed using the MTT assay. The annexin-V-FITC staining and propidium iodide (PI) staining methods were applied for the detection of apoptosis and cell cycle distribution using flow cytometry. The cellular level of ROS was measured using 7�-dichlorofluorescin diacetate (DCFH-DA) as a fluorescent probe in flow cytometry. The caspase 3 activity was assessed using a colorimetric assay Kit. Results: Echinacea purpurea (EP) root extract induced a considerable decrease in A549 viable cells, showing a time and dose-dependent response. The cell toxicity of EP was accompanied by induction of early apoptosis and cell accumulation at the sub G1 phase of the cell cycle. The elevation of cellular ROS level and caspase 3 activity indicate ROS-induced caspase-dependent apoptosis following the treatment of A549 cells by EP extract. The observed effects of EP extract on A549 growth and death were abrogated following blockage of CB2 using AM630, a specific antagonist of the CB2 receptor. Increasing concentrations of Cannabis sativa (CS) induced A549 cell death in a time-dependent manner, followed by induction of early apoptosis, cell cycle arrest at sub G1 phase, elevation of ROS level, and activation of caspase 3. The CB2 blockage caused attenuation of CS effects on A549 cell death which revealed consistency with the effects of EP extract on A549 cells. Conclusions: The pro-apoptotic effects of EP and CS extracts on A549 cells and their possible regulatory role of CB2 activity might be attributed to metabolites of both herbs. These effects deserve receiving more attention as alternative anti-cancer agents. Graphical abstract: Figure not available: see fulltext. © 2021, The Author(s)
Baghuk Mountain (Central Iran): high-resolution stratigraphy of a continuous Central Tethyan Permian–Triassic boundary section
Permian–Triassic boundary sections at Baghuk Mountain (Central
Iran) are investigated with respect to their lithological succession,
biostratigraphy (particularly conodonts, nautiloids and ammonoids) as well
as chemostratigraphy (carbon isotopes). The rock successions consist of the
Late Permian Hambast Formation, the youngest Permian Baghuk Member (new name
for the “Boundary Clay”) and the Early Triassic Claraia beds. Correlation of the
data allows the establishment of a high-resolution stratigraphy based on
conodonts with seven Changhsingian zones. Abundant ammonoids enable the
separation of ammonoid assemblages with the successive Wuchiapingian genera
Prototoceras, Pseudotoceras and Vedioceras, as well as the Changhsingian genera Shevyrevites, Paratirolites, Alibashites, Abichites and Arasella. Griesbachian and
Dienerian ammonoids are usually poorly preserved. Nautiloids occur
predominantly in the Wuchiapingian part of the section with two successive
assemblages dominated by the Liroceratidae and Tainoceratidae, respectively.
Numerous Early Triassic strata contain microbialites of various outer
morphology and microstructure. The carbon isotope curve (δ13Ccarb) shows a continuous late Changhsingian negative excursion
continuing across the Baghuk Member with the lightest values at the base of
the Triassic.</p
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