A novel diblock copolymer of (monomethoxy poly [ethylene glycol]-oleate) with a small hydrophobic fraction to make stable micelles/polymersomes for curcumin delivery to cancer cells

Curcumin is a potent natural anticancer agent, but its effectiveness is limited by properties such as very low solubility, high rate of degradation, and low rate of absorption of its hydrophobic molecules in vivo. To date, various nanocarriers have been used to improve the bioavailability of this hydrophobic biomaterial. This study investigates the encapsulation of curcumin in a novel nanostructure of monomethoxy poly(ethylene glycol)-oleate (mPEG-OA) and its anticancer effect. Tests were done to determine the critical micelle concentration (CMC), encapsulation efficiency, drug-loading efficiency, and cytotoxicity (against U87MG brain carcinoma cells and HFSF-PI3 cells as normal human fibroblasts) of some nanodevice preparations. The results of fluorescence microscopy and cell-cycle analyses indicated that the in vitro bioavailability of the encapsulated curcumin was significantly greater than that of free curcumin. Cytotoxicity evaluations showed that half maximal inhibitory concentrations of free curcumin and curcumin-loaded mPEG-OA for the U87MG cancer cell line were 48 μM and 24 μM, respectively. The Annexin-V-FLUOS assay was used to quantify the apoptotic effect of the prepared nanostructures. Apoptosis induction was observed in a dose-dependent manner after curcumin-loaded mPEG-OA treatments. Two common self-assembling structures, micelles and polymersomes, were observed by atomic force microscopy and dynamic light scat­tering, and the abundance of each structure was dependent on the concentration of the diblock copolymer. The mPEG-OA micelles had a very low CMC (13.24 μM or 0.03 g/L). Moreover, atomic force microscopy and dynamic light scattering showed that the curcumin-loaded mPEG-OA polymersomes had very stable structures, and at concentrations 1,000 times less than the CMC, at which the micelles disappear, polymersomes were the dominant structures in the dispersion with a reduced size distribution below 150 nm. Overall, the results from these tests revealed that this nanocarrier can be considered as an appropriate drug delivery system for delivering curcumin to cancer cells. © 2014 Erfani-Moghadam et al

Influence of shock wave propagation on dielectric barrier discharge plasma actuator performance

Interest in plasma actuators as active flow control devices is growing rapidly due to their lack of mechanical parts, light weight and high response frequency. Although the flow induced by these actuators has received much attention, the effect that the external flow has on the performance of the actuator itself must also be considered, especially the influence of unsteady high-speed flows which are fast becoming a norm in the operating flight envelopes. The primary objective of this study is to examine the characteristics of a dielectric barrier discharge (DBD) plasma actuator when exposed to an unsteady flow generated by a shock tube. This type of flow, which is often used in different studies, contains a range of flow regimes from sudden pressure and density changes to relatively uniform high-speed flow regions. A small circular shock tube is employed along with the schlieren photography technique to visualize the flow. The voltage and current traces of the plasma actuator are monitored throughout, and using the well-established shock tube theory the change in the actuator characteristics are related to the physical processes which occur inside the shock tube. The results show that not only is the shear layer outside of the shock tube affected by the plasma but the passage of the shock front and high-speed flow behind it also greatly influences the properties of the plasma

Frequency of ochratoxin A in bread consumed in Shahrekord

زمینه و هدف: با اکراتوکسین A مایکوتوکسینی است که به علت اثرات نفروتوکسیک، ایمونوتوکسیک، موتاژنیک، تراتوژنیک و کار سینوژنیک خطر بالقوه ی برای سلامت انسان دارد. این مطالعه با هدف تعیین حضور و میزان اکراتوکسین A در نان های مصرفی شهرکرد انجام شده است. روش بررسی: در این مطالعه مقطعی تحلیلی، 86 نمونه انواع نان عرضه شده در نانوایی های شهرستان شهرکرد از پاییز 1389 تا بهار 1390 جمع آوری و از نظر حضور اکراتوکسین A به وسیله روش الایزا مورد بررسی قرار گرفت. داده ها به کمک آزمون های آماری تحلیل واریانس یک طرفه و آزمون t تجزیه و تحلیل شد. یافته ها: اکراتوکسین A در 45 نمونه از 86 نمونه (3/52 درصد) نان بررسی شده ردیابی شد. محدوده غلظت اکراتوکسین A در نمونه های مثبت بین 19/0 تا 37/10 نانو گرم بود و میانگین آلودگی نمونه های آلوده 47/1±61/2 نانو گرم در گرم به دست آمد. سطح آلودگی 15 نمونه (4/17درصد) از مجموع 86 نمونه آزمایش شده بیش از حداکثر مجاز (5 نانو گرم در گرم) تأیید شده در قوانین اتحادیه اروپا بود. اختلاف آماری معنی داری بین سطوح آلودگی و تعداد موارد آلوده در فصول مختلف وجود نداشت (p>0.05). نتیجه گیری: نتایج این مطالعه نشان می دهد که بررسی منظم سطح اکراتوکسین A در غلات به خصوص گندم از اهمیت ویژه ای برخوردار است؛ زیرا بر این اساس می توان روش های مناسبی جهت کاهش آلودگی به اکراتوکسین A و بهبود کیفیت نان ارائه نمود

High prevalence of extended-spectrum β-lactamase (blaCTX-M-15) and New Delhi metallo-β-lactamase-1 (NDM-1) genes among high-level carbapenem resistance Klebsiella pneumonia: an alarm for our health system

Background: The extended-spectrum β-lactamase (ESBL) carbapenems-resistant Klebsiella isolates are considered one of the most significant challenging in the treatment of patients in hospitals. The aim of this study was to determine the prevalence of important carbapenem resistance genes ESBL subtypes and between K. pneumoniae from patients at hospital in Tehran, Iran.Methods: Fifty-four isolates of K. pneumoniae were isolated from Shariatee Hospital in Tehran from February 2013 to July 2016. Antibiotic testing was done by using the standard disk diffusion method and E-test MIC. The confirmation of carbapenemase activity was performed using an MHT and a new method called the carbapenem inactivation method test (CIM). Finally, a polymerase chain reaction (PCR) and sequencing of related genes was performed.Results: Our PCR data demonstrate that blaCTX-M group’s 40 (81.4%) genes were the most prevalent in our hospital followed by group genes blaCTX-M-3 (18.51%) and blaCTX-M-2 (20.38%). The distribution of the CTX-M group revealed that blaCTX-M-15 23 (42.6%) was the dominant subtype. The coexistence of multiple genes included blaTEM, CTX-M and blaSHV, and CTX-M The presence of blaNDM1, blaOXA-48, and blaKPC were identified in the carbapenem-resistant isolates, 22 (40.7%), 10 (18.5%), and 7 (12.9%) respectively.Conclusion: Our research showed that a CIM test for the first time in Iran is possible and has a high facility for the fast identification of carbapenem-resistant Klebsiella (CRK). We are encountered with the emergence of CTX-M, OXA-48, KPC, and NDM1 harboring CRK strains in our hospitals. Therefore, the treatment of patients infected with these isolates will be an important future concern in our clinical settings.Running Head: Resistance genes among carbapenem-resistant Klebsiella pneumoniaKeywords: New Delhi metallo-beta-lactamase-1, Klebsiella pneumoniae, Carbapenem, Extended-spectrum ß-lactamas

Trading Off Environmental and Economic Scheduling of a Renewable Energy Based Microgrid Under Uncertainties

Smart power grids are transitioning towards effective employment of distributed energy resources including renewable energy sources to address the growing environmental concerns related to the pollutant emissions of fossil fuels. In this context, this paper proposes the directed search domain (DSD) method to compute the combined environmental and economic dispatch in a microgrid with battery energy storage systems, photovoltaic plants, wind turbines, fuel cells, and microturbines. The DSD algorithm is implemented for a multiobjective problem to obtain evenly-distributed Pareto optimal points by shrinking the original search domain into hypercone. This paper computes the optimal unit commitment and the related power dispatch while simultaneously minimizing the total pollutant emissions and operating costs. The best trade-off solution among the entire set of Pareto optimal points is computed by using the Fuzzy satisfying technique. The uncertainties associated with the forecasting of prices, load demand, wind, and photovoltaic power outputs are accounted for by employing the stochastic programming. The empirical results indicate the potential of the presented DSD algorithm in terms of the objective values, solution times, and quasi-even distribution of the Pareto set

¿Globalizar Tenochtitlán? Geo-política feminista: la ciudad de México como frontera

Me di cuenta de que la ciudad se había convertido en una frontera cuando vi sus tatuajes: por todas partes, grafitis como los de Los Ángeles marcando símbolos y cicatrices a lo largo de las paredes y los edificios de donde el poder y la resistencia surgen a diario en la ciudad de México. Dicha ciudad es hoy en día tanto margen como centro del poder estatal nacional: la ciudad y sus residentes son parte de una frontera cuyos contornos oscilan entre el estilo de la globalización estadounidense hasta los de la civilización indígena mesoamericana. Visto así, el grafiti es un síntoma de conflictos mucho más amplios respecto a símbolos, significados, identidades y autoridad en un creciente espacio urbano transnacional y transcultural. Lo anterior no significa que la frontera México-americana tradicional de Juárez-EI Paso, por ejemplo, se haya reubicado en la capital, sino que otra frontera ha florecido en el corazón del país

Isolation of common carp ovarian follicular cells and evaluation of their endocrine activity in primary cell culture

To study viability and activity of isolated common carp, Cyprinus carpio, ovarian follicular cells (granulosa and theca cells), 17-α-Hydroxy progesterone (17α-OHP) and 17β-Estradiol (E2) levels were estimated in the culture media of cultivated carp ovarian follicular cells, using radioimmunoassay (RIA). Oocytes were isolated from the ovaries of female carp. Interstitial tissue was manually removed in order to obtain single oocytes surrounded only by the follicular envelope. Such a preparation was trypsinized at room temperature. Follicular cell suspension contained both cells and cell clumps. It was the mixture of theca (T) and granulosa (G) cells. The cells were grown as monolayer in 24-well microplates in M199 medium supplemented with FBS. Culture media were analyzed for estrogen and progesterone content by appropriate radioimmunoassay. Trypsinization of ovarian follicles resulted in the formation of the cell suspension which contained a mixture of G and T cells. The follicular cells attached to glass and grew well during culture period. E2 was the main steroid hormone secreted by cultivated cells. Estrogen secretion increased by 415.52 ± 25 pg/ml at the first 3 days up to 530.25 ± 55.8 pg/ml on day 5 and it didn't change significantly until the end of the experiment. 17α-OHP secretion, however, gradually increased from 23.84 ± 8.2 pg/ml at the beginning of culture up to 35.76 ± 5.4 pg/ml at the end of cultivating. As the result of the present study the fish follicular cells grown in tissue culture were steroidogenically active cells as expressed by the secretion of E2 and P4 and the E2 was a dominant hormone secreted by isolated follicular cells, which it correlated closely with vitellogenes stage

CFD modelling of velocity fields around a fume cupboard: Evaluating static and dynamic meshes with experimental measurements

This paper presents a comparison of experimental and numerical modelling results of the velocity field around a fume cupboard with a static and a dynamic mesh. During fume cupboard testing, components are required to move which mimic typical operating conditions, the amount of tracer gas released is then measured. This tracer gas is harmful to the environment and so an alternative is required. Advanced Computational Fluid Dynamics (CFD) techniques, such as dynamic meshing, have been utilised to replicate aspects of the current tests. The fume cupboard was tested in normal operating conditions and under the influence of a board inducing a wake close to the fume cupboard entrance. The velocity fields have been compared and show a reasonable level of accuracy with a percentage difference between experimental and simulated results of around 5% using both a static and a dynamic domain. This is an improvement on the 15–20% accuracy for detecting concentration of tracer gas using previous experimental methods. The aim of this work is to satisfy the scientific community and fume cupboard operators that CFD is sufficiently accurate to assess fume cupboard performance under real world scenarios

Prevalence of Gram-negative bacteria in ventilator-associated pneumonia in neonatal intensive care units: A systematic review and meta-analysis protocol

Introduction: Ventilator-associated pneumonia (VAP) is a common and potentially lethal problem among mechanically ventilated neonates in neonatal intensive care units (NICUs). The main pathogenic bacteria of VAP in NICUs are Gram-negative pathogens, which show a general decline in sensitivities to commonly used antibiotics, but their true prevalence is not known. Methods and analysis: We aim to provide a systematic review of studies measuring the prevalence of Gram-negative bacteria in VAP in NICUs. We will search PubMed, SCOPUS, EMBASE and the ISI Web of Science, as well as the Google Scholar search engine with no restriction on language. Full copies of articles will be identified by a defined search strategy and will be considered for inclusion against predefined criteria. Study selection and data extraction will be performed by 2 independent reviewers. Statistical analysis will include the identification of data sources and documentation of estimates, as well as the application of the randomeffects and fixed-effects meta-analysis models. This will allow us to aggregate prevalence estimates and account for between-study variability in calculating the overall pooled estimates and 95 CI for the prevalence of Gram-negative bacteria in VAP in NICUs. Heterogeneity will be evaluated using the I2 and ÷2 statistical tests to determine the extent of variation in effect estimates due to heterogeneity rather than chance. Publication bias and data synthesis will be assessed by funnel plots and Begg's and Egger's tests using STATA software V.13. This systematic review protocol was prepared according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocols (PRISMA-P) 2015 Statement. Ethics and dissemination: No ethical issues are predicted. These findings will be published in a peerreviewed journal and presented at national and international conferences. Trial registration number: CRD42016036048. © 2016 Published by the BMJ Publishing Group Limited